Good question. 12" would seem logical but I'd really want to try the 15" version. The three way model slips outside of an agreeable weight limit. The 15" 2 way version comes in at around 25Kg which is do-able for an all-in-one meaning that all of the backline can just stay at home. Also benefiting from feeding in keys (HPF'd) and vocals for a bit of spread at the back of the stage. I would dearly love a pair of Barefaced FR800's, they'd be amazing and would replace my BBII's. The Yamaha does have a pair of inputs and the onboard DSP, accessible from the back panel could possibly be a big thumbs up. Oh and the angled cabinet for monitor use is a plus.. yes I do have a stand here for angling cabinets upwards, but I have so many silly fiddly things to deal with on stage already it's wasting time and patience. Yup, for some gigs, I wanna turn up with my Helix, Monitor(s) and a box of leads.. or less ha ha!