I live in a Verizon heavy area and I've yet to meet anyone with an Epic or Evo FWIW. Mostly around here are BB, Droids and Incredibles. There are two people I work with that have the shift.
Same. Most of my friends are on Verizon and AT&T. The strange thing is back when I got my first cell phone in 1999, SprintPCS was THE carrier to be on. They were the undisputed leaders. All of my friends were on Sprint, and we all had similar numbers! Nokia was still the best brand phone to get. BTW, I'm talking about Boston area in case others' experiences are different.
Over the years, other carriers started to get popular, and people moved off Sprint. Then when Sprint bought Nextel and shot themselves in the foot, they earned a reputation for being stupid and providing bad customer service. Now, they are the small company (due to other companies' mergers) and still trying to shake off the bad reputation.
But the Evo at launch was no question the best Android phone out. Not sure how Sprint got that deal, but it's the best thing to ever happen to them. The Epic was released 3 months later and was on par with Evo awesomeness, but it touted a slightly different feature set: physical keyboard, better (subjective) display, faster GPU. But it had drawbacks as well: worse display (subjective), GPS problems, slow updates from Samsung.
Evo wasn't perfect either. The main issues were:
1) screen separation: this was a hardware defect from an early batch where the glue wasn't sticky enough to keep the touchscreen attached to the chassis
2) light leakage: the result of issue 1 above
3) charge ports coming loose and breaking after some use. Also limited to early shipments
4) a little crack forming in the plastic casing around the power button. Most Evos have this crack even though it doesn't seem to affect usability at all.
5) supply shortage. Neither Sprint nor HTC anticipated how popular this phone was going to be, so they ran out early. Meanwhile, people who had these hardware issues above had a hard time getting a replacement. Either there was nothing in stock, or they were getting a refurb, which often still suffered from these problems. We heard stories on these forums where people would be on their 5th (or more) replacement.
6) horrible battery life out of the box.
Most if not all of these issues are no longer relevant as far as I know. Demand for the phone has dropped, so supply was able to catch up somewhat. It's still not plentiful.
Over on the Epic side, they just got the official release of Android 2.2 (Froyo). Evo got it last summer, and like the Evo, there were some growing pains associated with the upgrade. From the looks of the Epic forum, people are still working out the kinks.
Overall Evo satisfaction is very, very high. If you look through some of the posts RE: will you get the Evo 3D, etc, a lot of people have a hard time justifying the upgrade when their existing Evo is so awesome. The other sign of Evo satisfaction is the large percentage of "Evo praise" threads compared to "Evo complaints."
Also you'll see that the Evo is the most active thread for any phone on these forums when launch date is factored in. The support here on the forums is incredible, especially when it comes to "all things root." Big homebrew community with TONS of customizations available.
Clearly I'm biased toward the Evo, but I think I've given valid justifications above for being so.