Those are 90 degree V-twins. With a single you can only balance about half of the reciprocating mass with the crank counter weights, because trying to do more adds vibration at 90 degrees to the cylinder. But if you have two cylinders at 90 degrees, then that is exactly the balancing that the second jug needs…so you can balance 100% of the reciprocating mass, and have a fairly smooth engine. There is still some “rocking” moments that don’t get balanced, but it is still smoother than any other V-twin configuration.
I’m with Johnny L.A. on ignorance when it comes to cruisers…in fact anything I have to say about them would constitute thread shitting. The one I am aware of that is smooth, quiet, powerful, and has good brakes is the BMW R12C. No longer in production as BMW riders are not interested in cruisers, and cruiser riders have no interest in BMWs…painting with a broad brush, but probably applies to 95% of each category. Price one of those out before you assume it is too expensive.
This is really going to get us to cherish each and every one of your posts from then on, as we will realize that it took you over 5 hours to compose a simple warning. 
My two cents? I’m the only one out of 4 guys in my generation who never rode. They always went on and on about high quality helmets. All 3 have gone over the high side more than once, two have been struck by cars. They own a Bell or a Shoei- both names have been mentioned through the years.
Buy the finest highest-tested helmet you can possibly afford. And, buy really good thick leathers. Remember- the cow’s already dead.
Cartooniverse
Dude, please. Had you done some research, you’d have spotted that I’ve made a similar comment in almost every motorcycle thread to which I’ve contributed. I’ve seen too many motorcycle accidents and heard of more.
Why would I do “research” when none was necessary. Are you seriously proposing that repeating the same thread-shitting behavior somehow makes it better? Get off your high-horse and at least attempt to address the OP’s question, instead of hijacking the thread bus and taking it down the highway to hell.
Quartz, Red Barchetta, cool it.
First of all, don’t settle on a bike until after you go through the training course. You may find that what you want changes. No harm in looking, though.
Second, remember that this is your first bike, not your last. Your primary criteria should be to find a bike that’s easy to learn on while being mechanically reliable. If/when you outgrow it, you can always trade up. Again, with some experience under your belt, you may find what you want changes. Better to go into it with the notion of trading it in after a season or two. Riding is a learned skill and you’ll become a better rider faster if you start small and build up.
I would reconsider used bikes. You can buy a trade-in through a dealer with service records and possibly a warranty, and have them take care of all the servicing if you don’t want to do it yourself. You’re going to drop your first bike (it’s almost inevitable), better to do it to a bike that already has a few scratches on it.
For a cruiser, I’d recommend starting on something in the 600-800 cc range. Big cruisers aren’t such good beginner bikes not so much for the power, but because they’re heavier. It’s easier to learn on a lighter bike. I’m partial to the Honda Shadow because my first “real” streetbike was a Shadow VLX (600cc), but any of the bikes from the big-four Japanese makers will do.
Besides the Shadow, I also suggest taking a look at the Triumph Bonneville. It has the different sort of classic, throwback styling of a British parallel twin, rather than an American V-twin. Then you’ll be a Rocker instead of a Mod. 
Except for the Thruxton, all of the Bonneville variants have a neutral, upright riding position that’s a bit better for control (and some riders find more comfortable) than the foot-forward style typical of most V-twins. Triumph also has a couple of models (the Speedmaster and the America) if you want something with a more traditional cruiser layout.
Style and marketing. I think the appeal of the cruiser is that when non-riders think of a motorcycle, they think “Harley”. To the uninitiated, all bikes are either “Harleys” or “crotch rockets”, and cruisers are the only “real” bikes. I’m forever explaining that no, my V-Strom is not a sportbike, it’s a dual sport; and then explaining what a dual sport is (and then I’m usually met with a glazed stare and the follow-up question “So it’s a cruiser, then?”).
Don’t get me wrong, cruisers aren’t bad bikes for what they are. Only that a lot of people don’t know there’s a whole world of other bikes out there. Many of them just want to buy into the biker lifestyle scene, and for them the bike is just an accessory.
Here’s a breakdown of the major bike types I wrote (a bit tongue-in-cheek) for another message board:
Cruisers are bikes in the classic Harley mold. One of the top two most popular categories. Think Easy Rider, black leather, and polished chrome. Meant for getting where you’re going in style. Tend to be heavy and have big motors, but there are notable exceptions. The choice of grizzled old-timers and white-collar middle management alike. If you want to be a wild rebel, or just look like one, this is your bike. Choppers are a subtype of the cruiser category where you start with a perfectly good bike and render it unrideable. Examples: Harley Davidson (just about any), Honda Shadow.
Sportbikes are the plastic-covered race replicas. The other most popular category. Meant for going fast, not too comfortable for around town riding. Generally the worst type of bike for an inexperienced rider, though ironically the choice of unskilled 20-somethings. Squids, as we like to call them. There’s a reason you hardly ever see old sportbikes on the road. Truly awesome in the hands of a great rider. If you want to carve up the twisties or just pose with the import tuner crowd, this is your bike. Examples: Kawasaki Ninja, Suzuki GSX-R.
Standards are your ordinary, generic bike. Once the most dominant category in the days of the Universal Japanese Motorcycle. Now a small niche. Your basic bike with no bodywork, few bells and whistles, and a neutral riding position. Everything you need, nothing you don’t. The choice of the rider who wants a practical, no-nonsense means of transportation. If you want to be an elitist who scoffs at poseurs on bikes they can’t handle, this is your bike. Good commuter or beginner bike. Examples: Suzuki SV650, Triumph Bonneville.
Touring bikes are to motorcycles as conversion vans are to cars. Meant for eating up the highway miles with luxuries not found on other bikes. Equipped with gadgets like cruise control, intercoms, stereos, CD players, CB radios, satellite radio, satellite navigation, heaters, air conditioning, weather radar, kitchen sinks. The choice of gray-haireds spending their kids inheritance on a multi-state odyssey. If you want to cross the country in comfort, this is your bike. Examples: Honda Goldwing, BMW K1200LT.
Sport-Touring bikes are somewhere in between a sportbike and a touring bike. They are sporty but with less aggressive ergonomics, a genuine 2-passenger seat, and various luggage options. The choice of the older sportbike rider who’s back can’t take it anymore. If you want high performance but without sacrificing comfort and practicality, this is your bike. Examples: Honda 1100ST, Ducati ST3.
Dual Sports are bikes that are as home off road as on. Some are practically dirt bikes with turn signals, while others are more suited to pavement and only mild off-road excursions. The choice of the globe-trotting adventurist who consider a tent and a passport essential riding gear. If riding the full length of the Pan-American Highway from Alaska to Chile sounds like a good idea to you, this is your bike. Their ruggedness also makes them great commuters and beginner bikes. Examples: Kawasaki KLR650, BMW R1200GS.
There are a number of other types and subclasses (streetfighters, adventure tourers, supermotards, etc…), but these are the ones you’re most likely to come across.