After over a year of using these in tight spaced venues, I've learned that they are a real work horse that get the job done. We've used them with various microphones and acoustic/electric instruments with great results. Following are some photos of venues where we've used them.
The Kustom Powerwerks PW50 is lightweight, powerful, clean and stand mountable. As you can see in the following photos, it does well in tight spaces. It even has built in phantom power for condenser microphones. You can use the 1/4" and XLR inputs at the same time on each channel. With a built in mixer for two microphone/instrument channels and a third channel for MP3/CD, It's a bargain that can handle crowds up to about 60.
At Hulaville's closing party in San Clemente it was packed with people, so we used two PW50's, linked by a 50' microphone cable. You can see the one on the right, but not the one on the left:
A trial run at Jolly Roger in Dana Point, (now closed) we used one that you can see on the left (it was a long flight of stairs bringing the equipment up):
A trial run at Bubba Kahuna's in Dana Point you can see the one in the center over one of the TV screens (they had the sound turned off on the TV's):
At Ukulele Sundays current venue at Molly Bloom's in San Clemente you can se one on the right and one on the left.
The Kustom Powerks PW50 really kicks and cuts through the ambient noise of a crowded venue for a pittance of cash outlay. They are a great backup for more complex systems. Keep one of these, a speaker stand, a microphone and a microphone stand in your car for impromptu gigs. Ric