Bob-
This is what I decided to do, based on happenstance and research but without listening to all the candidates which I what I really should have done:
I got the Mackie 406M powered mixer. I had tried one at a friend's house and it seemed good to me; plus I nabbed one (new) on ebay for $420, which is $150 less than the lowest prices you see on the net. I wanted the eq and effects capabilities it has also. You can spend a little less or a lot more. People who use Mackies always seem to like them, although audiophiles seem to hate them and tell horror stories about them (even though audiophiles are full of extremely helpful knowledge, I always take their conclusions with a grain of salt since they hear things that 99.9% of the population doesn't).
Anyway, I think the speakers are going to be more important in determining the sound. In my experience the type of 15"/2" speakers that Mackie, Yamaha, etc etc peddle for use with small powered mixers are inappropriate for small acoustic acts. Much too boomy and boxy. My research confirmed that such a set up sacrifices mid-range and vocal clarity. I settled on the Electro Voice Sx100+ speakers, which I ordered for $301 each at fullcompass. They are 12" bottom and 1" titanium horn (it works for golf clubs at least) and the specifications at least made it seem like EV thought about what it was doing. EV isn't a sexy brand but the few people who I ran into that have used them loved them. And they only weigh like 33 lbs. You can spend much more on EAW, Bag End and the like but I think I'm getting quality.
Also the Mackie is 200W (they advertise it as a 500W mixer but actually it's 250 per channel at 8 Ohm, which means 200 at 4). And the EV is rated at 200W continuous. I'm told that if the speaker's capacity is too high in relation to the amp power it taxes the speaker; likewise, unless you are a pro, it's dangerous to hook up speakers to an amp that dwarfs its capacity.
I'll let you know how it sounds....
