VOX in a box
I have a Wampler 30-Something, as well as an AC30CCX and an AC30HWX to compare. The Wampler is damn close. My ideal tone on the ACs is 10 o'clock on the bass and 2 o'clock on the treble and treble cut at 50%. The Wampler is tuned so that that setting is nearly 12 o'clock for all on the pedal.
Also, the Wampler does Queen really well with everything dimed, and has an onboard boost. There's also a switch that changes the color from AC15 to AC30.
I've tried Tech 21 and Line6 but the Wampler is closer to the actual amp sound.
Strangely, I've also discovered it makes a great direct pedal for acoustics that use those thin twippy piezo pickups or Fishman/magnetic type. My SJ200 and my Seagull S6+ with a Fishman RareEarth sound natural like they're mic'd if I run into the Wampler then a DI to the board.