I love mine. Initially had a couple problems (one of them was hardware related so the box needed to be sent back to Samsung). First had buyers remorse because I came from a Hughes E86 which worked great but ran hot enough to heat my whole house. Samsung support was absolutely incredible, went out of their way to make sure the box worked as it should. They fixed a red push issue (that was hardware), along with funky access card error and PSIP data issues (those were software).
The E86 it replaced actually melted the paint on my DIY component rack (the rubber feet on the E86 were stuck to the paint itself). The Samsung barely gets warm to the touch (dunno why a previous posters box gets so hot). Its completely stable except for an occasional guide slow-down, which I believe has something to do with leaving it on an OTA channel that turns off their signal overnight.
New boxes may be better, but when I was thinking about replacing the Samsung, after reading all the reviews and such, you could end up with more features but also a lot more issues too. The Sammy has served me well, and I will hate the day D* forces me to "upgrade" to their HD replacement box.
-Chris