I had an Epic for the past 6 months, and it was nothing but a PITA! I would randomly lose signal, go to roaming, not be able to place a call... The GPS never worked. I got it because I had trouble using the touch keypad on the Hero, and convinced myself that I couldn't live without the physical keyboard. I hated every minute of the Epic.
I just got the Evo 2 days ago, and I am so in love! My only beef is that it was super easy to root the Epic and I've been reading through all the threads on here and am thoroughly confused on rooting the Evo.
I know there are alot of rabid Epic lovers, but honestly, Samsung cannot touch HTC in quality.