We're real happy with our K12s. (We have the originals, not the V2 models. Haven't seen a need to upgrade.) We also use K10s for wedge monitors. The K-models have plenty of clean power for our needs. We're an acoustic/electric classic rock cover band. We're running vocals and both electric and acoustic guitar processors direct to FOH with no backline. The bass guitar is a Washburn acoustic, run into a 4x10 combo amp, and a little bit DI'ed into the FOH for better definition. We don't run drums through the PA for most gigs, but the drummer mics his kick drum and runs it direct into a K8 on the "Deep" setting, pointed at the wall behind him. It's sort of a mini-sub, adding a touch of thump to the kick.
Even though we don't typically use subs for the small places we play, we usually tame the boominess with the "Exernal Sub" switch on the K12 and K10s, which is just a low cut filter. For larger venues and big outdoor shows, we add subs to the setup and mic the drums more completely.