Just to add to the anecdotal evidence:
Out of 108 chars, nine are fully equipped with sets, though around 20 others have partial setups, thirty in some incomplete state. I tend to hit 50, respec, fill in with generic 50 IOs. Then those characters get filled in as they play.
Three of my chars are fire farmers ( brutes, one tank), pretty much equipped with what I picked up with all those other chars. Tried out a few different styles and have a few others that could be outfitted, but I don't do it very often so hasn't been a priority. I do tend to run them thru the various content to at least get the stat accolades, and for the most part, they seem to do just as well if not better as any of my generic IO builds.