HTC 8125 / 8100 / MDA (USA) / K-JAM / P4300 (Wizard)

I need some advice. I currently have a BB pearl and I love this phone but I can't surf ebay and look at items I am selling or wanting to buy. I guess it doesn't support those pages or something. Even my old sidekick 2 could do that! Anyways, can anyone advise me as to trading it in for an MDA? Do they have good battery life, good signal, easy to use?? Any advise would be greatly appreciated, thanks!