I've been researching this topic for like nearly a year, I like the idea of baitcasters, I haven't really had much hands on experience with them though, but after reading lots of articles, posts, and all sorts of stuff, the only real advantage I can find to an overhead is the ability to pick up bites on the drop...even then, I've picked up fish on the drop with my spin set, but then I've also flicked the bale arm over to find a fish on the end that I new nothing about!
I think if anyone was completely objective, it comes down to personal prefference, or what they're used to, there's no doubt, for example, that a spin set is less prone to tangles, and overall is a much simpler set-up, but then the level of control over your line on a baitcaster is cool!
Learning how to control a baitcaster, casting, preventing over runs ETC, is going to take some practice, so the question should be, do you want to spend time learning a whole new way of fishing when you could be spending that time just fishing?
There will never be an answer to which is better, just go with what you want to use...learning how to use a baitcaster could be a whole lot of fun, but it could also turn out to be not your cup of tea, in which case, you've bought a expensive rod that is no longer any good to you!
Find someone that will lend you a baitcast set, PJ seems to have a few kicking around, he might even give you some tips, being the fan of baitcasters that he is!