Meat MixerI'll add my recent experience to this discussion.
This past weekend I bought a Cabela's 44# mixer - was on sale a the local store, price was $249. Nice part is it mates with my grinder motor.
My main concern was whether or not it would work with smaller batches - in the 10# range. User reviews on Cabela's site and other sites was mixed. But, I'm happy to report that it worked great. I did the initial grind with a two hole kidney plate, so the pieces were quite coarse - placed the entire 25# batch in the mixer and mixed for about 7 minutes to incorporate the fat/lean uniformly. The paddles moved the meat around nicely, folding it consistantly between the rotating and fixed paddles.
I split the batch in half to make two differently flavored 12# batches. I mixed the spice mix and non-fat powdered milk with about 1 1/2 cups of water and drizzled it through the slot in the cover with the paddles in motion. I ran the mixer about 5 minutes, was somewhat skeptical about any mixing taking place, but when I stopped the machine and examined the mass, I found the spice mix was well distributed throughout the meat. While mixing, it looked like the meat was just being moved left and right between the paddles without any turning over/folding, etc. But, it indeed did mix the spices nicely. And quickly - the meat was still about as cold as it was when it went into the mixer.
All in all, I'm very pleased with this machine, guess I should post this same account on Cabela's user review. If I had to guess, those folks that reported poor mixing likely didn't mix the spices with water, or, they were using a smaller volume of meat than 10-12#.
Oh, and clean up is easy - the paddle pops out easily, lay the tub on it's side draining into the sink, and use the spray head to flush out the residue, wipe with a hot soapy sponge, rinse again and call it good.