No need to rush to answer (just joking...) 
from Amazon user...
[Blocked Image: https://images-na.ssl-images-amazon.com/images/S/amazon-avatars-global/default._CR0,0,1024,1024_SX48_.png]
Chuck
4.0 out of 5 stars Good for small and medium sized venues
Reviewed in the United States on May 8, 2018style: 600ISize: PA SystemVerified Purchase
Works great for rehearsing our new group. We will routinely play in the same venue, capacity about 225 folks. Plenty of volume for that. Powered mixer is easy to set up and use. It's too bad the mixer, once removed from the back of the speaker, doesn't adapt to a stand. It would be handy to have the mixer on a stand. They do sell stands that will accommodate the mixer, but you have to attach a bracket to the mixer to connect it to the stand, and then you have to detach that bracket again (or so I have been told) to stow the mixer back into the speaker. Overall, the kind of quality one routinely expects from Yamaha...good.
In terms of power, it depends how loud 'really loud' is. For most purposes, it would likely be ok for rehearsals but once that volume starts rising, it can be increasingly hard to achieve separation in a confined space. Having multiple sounds coming from one source can lead to frustration and arguments; that's effectively why individual mixes are preferred.
But it's all very subjective, I've rehearsed in tiny rooms with just two small powered wedge monitors and full rock band. Sure, the rest of the band don't hear the vocals so well but the singer can.
