I'm wondering if a aluminum bunk trailer would be a better choice then a galvanized trailer with rollers? I've noticed that a lot of boat trailers have the bunk rather then the rollers
It's kinda' "6 of one, or a half-dozen of the other." As the gang is saying, in your size boat it's really all about preference.
There's an ongoing (and likely, everlasting) debate on one vs. the other. Aluminum trailers are generally lighter than a galvanized, which can be a benefit (though some would say when launching in rougher water they tend to float around on ya'). If you're in salt, I think Aluminum is the preferred for corrosion resistance. Typically, I think galvanized is cheaper if you're buying new ... but I'm not sure how true that's holding these days.
Bunks vs. roller are "fightin' words" as well. Both'll hold the boat just fine, but the question becomes how much easier ... harder ... too easy ... or too hard ... it is to get the boat on and off the trailer. A boat will slide down rollers real easy, but maybe too easy if the ramp you're on is too steep (as an example). Some will say bunks give better hull support ... and on the discussion would go.
For a 14' boat on the ramps I have around here: I'd be lookin' for a aluminum bunk trailer.