I really liked my BA when I bought it. I had a the crappy HP from Tmobile which gave me nothing but problems, so getting the BA was great. I still like it. I saw the Universal in person and while it looked cool, I was getting tired of having a big pda/phone so I really didn't want to buy it. Its bigger and heavier than my BA, so that pretty much turned me off.
I read about the K-Jam on The Register and 48 hours after that had one in my hand. I really, really like it. I was looking for a smaller device than the PDA2K and having seen the i-Jam before, I thought this should work perfectly....and it does. I'm really glad I didn't go with the Universal. But, to each his own. The keyboard on the K-Jam is great also, screen is good, speaker is loud, speakerphone is perfect, camera is good....I really have no downsides to it....except I can't get on my frigg'in wifi.
If you don't mind the size, go for the universal. If you're tired of the size and weight of the BA, go with the Wizard. Overall, I feel the Wizard is a huge improvement over the BA. Phone and BT work perfectly! If you buy it from Expansys, you have 14 days to play with it. 14-day return policy.