I agree with mrspeedmaster's points on why Galaxy S phones are better in those areas. Better graphics capabilities, better sound, and of course everyone is all about that gorgeous SuperAMOLED. But the Evo has its strengths over Galaxy S phones as well;
1) The UI. Now, this is totally preference, you love it or you hate it, but I strongly dislike Samsung's TouchWiz. I see it as a weakness, compared to Sense's polish.
2) Dual cameras.
3) Dual LED flash, as opposed to none. I know about the night mode and everything, but it really isn't the same for total night shots.
4) All the gimmicky extras, like the kickstand and HDMI out. Well the kickstand isn't that gimmicky, I actually use it a lot to keep the phone's camera lens off hard surfaces.
5)The screen size. I've played with a Vibrant prior to getting my Evo, and the extra 0.3" does make a difference. When I first my Evo, I had this "WOW, this is HUGE! I LOVE it!" reaction that I didn't quite get with the Vibrant. Maybe it's the way the bezel is large on the top and bottom that gives the illusion that the screen is smaller, whereas the screen is almost the entire front surface on the Evo.
Both phones have their strengths and weaknesses. I prefer the Evo, myself. But I think when you consider the shortcomings of both, it's a draw. It all comes down to preference.
. But yeah, that is really steep just to see your phone on the big screen. I don't think it's worth it...