Mid-High Level is my preference. I haven't seen a reason to go Epic. Most of the folks in my campaign started at 1st level, they are now pushing 8th - 12th. The NPCs keep pace.

I very rarely use official modules and when I do, they are very heavily tweaked. I think we used maybe two scenarios from "Legend of the Hero Kings". I ran the Sword of Roele with major modifications. The other releases I used for occasional inspiration or for NPCs.