Pasta, I too have played around with both the Epic and the Evo and as you mention both phones are out of this league when compared to the Moment or Pre. My only concerns with the Evo are its size and the screen. I wish HTC would have put an AMOLED screen on it and reduced the size to 4". It feels too big to hold next to the ear. I didn't know about the GPS issues with the Epic because I was going to use my upgrade in a month to get it. As the owner of a Moment, I too am frustrated with how slow Samsung is with fixes. Thank God for Noobnl and the like because with his latest ROM and inxane's kernel, my Moment is 90% better than it was before.
Among non-4G phones, the Optimus is a very good choice and free is always good