I am about to buy a pair of active speakers for our rehearsal studio (18 square metres), mainly for voice and acoustic instruments to come out. (We also have drums, electric bass, sometimes guitar or keyboards but we still don't know if it would be better for all the instruments to come out of the PA speakers). I made a little research and found:
Mackie SRM 350 539euro
Mackie SRM 450 ...
DB technologies Opera live 402 459euro
DB technologies Opera live 405.
Samson DB 500A 415EURO

If anybody has listened to the above speakers, which of them sound less harsh?

And for nother price category:
TheBox PA203-12A 198euro
TheBox PA110A 155euro

Also which of them could be used for small live situations (in a club or something)?Will we need subwoofer when we jam in the 18 square metres studio? What about a gig in a small club?
If one speaker claims frequency response at 55Hz or 50Hz -3db, and another one at 60Hz is it of a big difference ?(as far as it is related to the need of subwoofers).
What about the different sizes of woofers? (10inch like Mackie SM 350, 12 inch like Mackie SRM 450 and Opera 402 or 15inch like Samson db500a, or Opera 405.