Pros:
All the vehicles are pretty cool, and most of them have some deadly weaponry.
The aforementioned lack of legal ramifications for your actions.
Cons:
As it turns out, walls and even the surface of the Earth (or whatever planet you happen to be on,) are paper thin. Errors in reality can leave you stranded on the wrong side, or falling to oblivion.
Pro’s:
Lots and lots of crates everywhere. Some of them have goodies inside if you smash them. Go ahead- nobody minds.
The New England Patriots have won the Super Bowl 4 years running. That trade for Ricky Williams is really paying off.
Cons:
While you have teammates with you during most attacks, you will spend more time saving their dumb butts then you would like. Heck, it may have been faster to leave them behind while you clear the rooms without them.
You can often shoot the guard right next another one, and the still live guard only seems mildly interested in the corpse next to him.
:dubious:
While almost all doors are locked, there are only 4 or 5 five different types of locks. These and all the keys are conveniently color-coded with bright colors. Unfortunately a key can only be used in one lock, then it disappears into thin air.
I’d run around in dark rooms eating glowing dots and running away from ghosts.
Wait, isn’t that the plot of Scooby-Doo?
killing things will improve ALL your skills, not matter how unrelated to fighting. want to improve your magic skills? kill things!
cooking skills: kill things
sneaking skills: kill things
speaking skills: kill things
got a math test tommarow? don’t READ your book! just use it to wack the family cat!
Sentries that block your path follow amazingly predictable patterns.
People you’ve never seen run up to you on the street offering vital information.
No objective, no matter how strategically important, will be protected by more assets than you can eliminate with materials already provided to you.
Every time you take a particular action, John Madden makes the same obvious comment.
Pros:
Crashing my car into anything would cause no injuries to me as long as the car doesn’t catch fire. In fact I’d still be able to get out and run from the police just as fast as I could before.
Almost all guns have an auto-aim feature as long as you press the right button.
Having sex will make me feel much, much healthier. With each thrust in fact… 
Walking into an army base wearing a police uniform will allow me to steal a tank or helicopter without anyone batting an eyelid. At least until I start blowing things up with it.
Despite Public Enemy Top 10 status, a quick car respray and a change of clothes and I’ll be unrecognisable to the police…
Cons:
Oops. Forgot to add to the cons:
My vision would go black at odd intervals.
I would see the light…
And be booted back to my OS screen.
Time to meet the maker.
Philosphically, I would say that LIFE CHEATS ME!! Then, as if someone threw a controller against a wall, I would run in circles.
Cons:
Pros:
Pros
You could enter people’s houses at will-almost nobody bothers to lock their doors. You can also rummage through their stuff without them having any objection, barge in on them in their bedrooms and they will merely say some mundane piece of information about their family life or the state of affairs in the village/town/city that you are in.
Cons
There is a good chance you will get drafted to fight in a war in which you are the only on fighting on your side. If you are lucky, you will be able to pilot a WWII-vintage fighter, but most likely you will be givien a rifle and dumped in some god-forsaken jungle only to fight your way through and finally have to defeat the evil dictator of the country yourself 
Scuba_Ben, I’d venture to say that you’re probably as old and creaky as I am.
<-(
Dunno about you guys, Larry and Ben, but I could never get past the second dungeon.
As for my list of pros and cons:
Pros–
Cons–
Pro: Everywhere I go, I have a cool rock-n-roll soundtrack.
Con: Unless it’s rap.
Pro: If I hit nitro turbo boost on a ramp, I can jump halfway across a major city.
Con: But the pedestrians will completely ignore my approaching vehicle until I crush them.
Or maybe that’s a pro. Hmmm.
Pro: All the boring bits of life are missing.
Con: The exciting bits don’t have much variety.
The more stuff I eat, the healthier I get.
I can wander around, breaking things open, and keeping anything interesting I find inside. But if I find a whole area full of really good stuff, I should be afraid… because something BIG is about to show up and totally kick my ass…
It is not possible to shoot my friends.
Women have huge breasts and square butts.
If I’m not strong enough to use any given object, I can just put it in my pocket and carry it around until I AM strong enough to use it…
THE DOWN SIDE: Bars only serve as meeting places. It is impossible to buy a drink in one.
Con: vast areas of the world are covered in friggin frictionless ice.
Pro: Sewer pipes lead into really cool hidden places.
Pro:
I could leap across 30 foot chasms and save myself by grabbing onto a ladder while falling at speeds that would surely rip my fingers off.
Cons:
Thirteen-year-olds would taunt me for being a n00b my first couple weeks of life. Then I would hang out with them for hours at a stretch, doing nothing but beating them up, stopping just long enough for them for them to rise to their knees and curse me; then I would beat them again. They would get more and more desperate, as their egos are in peril, and I would keep kicking them down until some big thug came along and beat the crap out of me and I crawled away in shame, muttering plans of revenge.
Oh, wait.
Invisible people want to kill me.
When I off the captain, the security team that comes after me is invincible. Nevermind that they are wearing the same freaking body armor as the other soldiers I killed for fun or that I am lobbing grenades at them and pumping hundreds of rounds into their bodies.
Or become incredibly skilled by saving, learning something as fully as possible, and them restoring. You know have that knowledge instantly, in essence.
“How did you learn to play the piano overnight?”
or it would be wonderful on tests.
Jesus. I literally fell out of my chair laughing at that one.
My apartment has hardwood floors, which made this somewhat unpleasant.
Pro: No matter how many people you killed, the bodies would disappear shortly after death and not make the place all stinky.
Con: Females would have no purpose other than walking back and forth along a prescribed route in towns and occasionally giving you hints and pointers.