I used two Bose L1 for several months, and, in my opinion, the stereo sweet spot is enhanced substantially...why else would I spend a lot of extra money...just for a small improvement?

I don't mind spending money, but I do hate to waste it.

I didn't use a mixer...just straight out from the keyboard's L and R...when someone sang, we used the keyboard's mic input.

Regarding the Compacts...

I used (actually demo'd) the Bose Compacts in a large hall, as well as in the store proper, and whilst it was being tested, two (or perhaps three...I can't remember) of the people present, ended up buying (or ordering) two Compacts, where they had initially been interested in getting just one.

So...it wasn't my imagination.

The bigger L1's are the way to go if you expect you will need a fair amount of oomph, but the Compacts are still a very capable system.

I haven't bought mine yet...waiting for some gig confirmations....right now I'm using my Yamaha MS60S powered monitors.