I voted Yes, but let me explain why....
Since you already have the Epic with a QWERTY hardware keyboard, then you more than likely like that feature. The Backflip is currently the only Android option with a hardware keyboard on AT&T (here's hoping...). If you're OK modding your phone and want to tackle rooting it then you can delete some of the AT&T bloatware and have it running a bit quicker than stock AT&T. It's also one of the least expensive to purchase from eBay, I got mine in a brand new state for about $160. (Arias are around $300)
I got it for the keyboard, but otherwise I would go with an HTC (Aria) if available. Afterall, the BF is still waiting for the official 2.1 update, and that's where it will end; 1.5 has some issues, but nothing that makes the phone unusable. After I rooted mine I started to like it more.
My 2 cents.