Believe me, I really wanted the AC light to be the right light for me. I'm a loyal AC guy. I just had to weigh the facts. The AC is "just" enough to do the job in a 2x4, yes it has UV, but is UV a fad? We been growing pretty dam good weed without it for years. UV is still in the "maybe" realm, still no science to prove it. For the same price the SP 3000 is 42" long and all tests say its possibly even over kill for a 2x4. I'll take over powered vs under powered any day of the week.
But we all have different situations, like tent height, which we each have to take into consideration when we go light hunting. I recently sold my AC 4x4 and went with a spider farmer 2x4, which is actually a 28"x 54" inside. I wished like hell AC or Gorilla made a over sized 2x4.
Good luck with whatever you go with.