Definitely give it a try! Many bass players disagree with this, but as both a guitar and bass player, I find the bass to be quite a bit easier. It is more physically demanding in some ways–heavier instruments usually, and sometimes bigger stretches for the fingers. Still, I find it easier overall, and much, much more fun. Simpler lines, for the most part, and fretting is similar, except that bass players don’t often play chords. I do sometimes, but it’s hard to play a bass chord that doesn’t sound muddy.
The roles of the instruments are different, of course, and sometimes guitar players switching to bass tend to approach the instrument as they would a guitar. That isn’t always a bad thing, but playing too much “lead bass” does annoy other band members.
I have two fully acoustic basses, and one semi-acoustic. (Nitpick: I call the Dean bass you linked to acoustic, because it can be played without an amp. A semi-acoustic has piezo pickups and a semi-hollow body, but must be amplified to be heard. I have one of those, too.) I love those acoustic basses, because I can pick them up and play them for 2 minutes during a commercial, for example, without fumbling around with cables and amps. I play mostly by myself, and an acoustic is fine for that, but it doesn’t cut through much with other players. I can keep up with one acoustic guitar, but that’s about it. More than that, and you’ll need to plug in–to a bass amp! You’ll blow the speaker in a guitar amp.
Five-string? I do see the value of them–not so much for that low B, but for the ease of playing notes without switching positions. Also, an open low E won’t sound as fat as a low E on the fifth fret of the B string. Still, I play only 4-strings. I like the simplicity and balance of them, and strings are easier to find.
Speaking of strings, that Dean is a medium-scale (32"). A bit easier on the stretches, but long-scale (34") strings are more plentiful, in more varieties. I like the nylon tapewound strings for acoustic bass–a real deep, woody sound. My favorites are LaBellas, available cheap from the Carvin website.
One last thing: the first time I tried a fretless bass (also acoustic) at a music store, I went straight home and ripped the frets out of my bass. Since then I’ve bought three more basses, all fretless. They aren’t for everyone, but for some of us, nothing else will do. At least try one in a music store before getting a fretted bass. They really aren’t that much harder to play.
Recommended reading: Bass Guitar for Dummies, by Patrick Pfeiffer. You could also check out the activebass and talkbass forums. Welcome to the deep end!