I owned the M900 for a while before deciding going to in-ears was probably a better use of my money. It's a fantastic amp. As @Higgie says, the tone control is the secret sauce of the amp, and makes it much more pleasing to use than the B*K or Vintage pedals - I bought the Vintage Ultra after the M900 and it just wasn't as nice. It's a really versatile design, but be aware it has its quirks - like the volume control controlling the DI output level, something that was corrected in the M500.