Coming from a Sidekick, with one of the best keyboards on the planet (IMO), I think you'll be disappointed using SureType on a Flip. So, I'd rule that out. I have an Eternity on my AT&T account, and it's a cousin to the Behold. There isn't much not to like about it, however, you may find that your e-mail accounts are limited to what T-Mobile provides through their e-mail interface. A "master code" has been published around the forums, and allegedly, that will allow full POP mail account access, but I don't think it's a perfect solution. So, the e-mail provider(s) you use, might be a factor in the Behold purchase. I had a G1 on my T-Mo account, and found that the wi-fi was flakey, the battery life was awful, they keyboard was mushy, and the "chin" made it a pain to type on that mushy keyboard. Take that OS, and put it on different hardware, and it would likely be top-notch. For now though, I'd pass on the G1. Honestly, with you coming from a Sidekick, with a hardware keyboard, and the ability to poll whatever e-mail accounts you like, I think a full QWERTY BlackBerry is your best choice. I'd suggest the 8320.