Stay away from the kitchen aid or anything like it. Nothing against kitchen aid (wife owns one & the grinder attachment), but it's not the right tool for meat processing. I have the Cabelas #22 1HP. It paid for itself after the 2nd season of use. I've owned it for 5 years now, and it has a minimum of 45 - 50 deer through it now, not counting other game processing work. Beyond burger we make our own sausage and brauts, and use the grinder for all the stuffing work. In the summer we usually grind a pork as well. I and my wife don't regret the purchase at all. We had a 5HP Hobart prior to this and it was just to massive for a home/family use.
We learned early on that if the meat is to warm (above 40F) and the cuts are small then it will not feed very well at all and mushes the meat through the plate versus grinding it. We don't freeze but do "soft freeze" our meat before grinding. This alleviates feeding issues.
I would seriously look at the LEM products as well. Their "BIG BITE" screw interests me, and I believe they make quality products for the home user. Their customer service is good as well when I've spoken to them.
If you buy one, regardless of brand, make sure you buy a foot switch as well if you will be processing lots. The switch increases efficiency and alleviates one from having to constantly turn the grinder switch on and off. Not to mention when you are stuffing casing the foot switch is a must have. Also I suggest that you have a dedicated plate/knife set for each plate size. The knives and plates wear into each other, and imo a dedicated set will minimize wear on the knife when swapping plates.