I got the Hornady one that does brass and will accommodate an M4 upper. Pros: it works. Cons: it doesn't work for long. Seems like a transducer or something worked loose and it "rattles" or vibrates a little when it's on now. I tried to use it to clean 10,000 of pieces of .50 brass and it did a good job, no AMAZING job, but after running all day I had to switch to a cement mixer (trick with making those work is to use hot water to wash and do the final rinse).
I did find that if you use Kroil in a pan and then put parts in that and then submerge that into the water, or sealing parts in a jar with kroil and placing in the water, tended not to damage finishes or aluminum at all but cut through carbon enough to make a filthy .22 can nearly wipe clean.
If you're really into the US cleaner, I'll give you a deal on mine. It still works fine despite the rattle, basically new, but it's just not industrial enough for me and the heavy duty industrial models aren't cheap. Finally, there isn't much to one, just a few transducers stuck to pan of water with a heater wired into it. Some buttons and viola! In short, I bet you could build one far more powerful for far less money if you DIY it. They're very simple.
They do work great though and they do it all on their own, now you got me to thinking maybe I should take all this damn brass to a US cleaner business and see if they'll just knock it all out at once --it'd be worth it to not spend days and days just cleaning brass and I could focus on loading it instead. Whatever you do, don't ever get an M2HB, that's the gun that owns you.