I would recommend looking at a horizontal stuffer in the 15 to 25lb range. I have a 11lb vertical stuffer and end up with about a pound and a half of waste that can't be stuffed due the the angled tube at the bottom. I have tried the ice, bread, etc. and never really had great results in getting the remainder of the product cased with these methods.
I find that the 11lb stuffer works for what I do (Snack stix, summer sausage, brats, etc.). I run out of casing about the time I need to refill the stuffer, so having a 25lb unit wouldn't really benefit me all that much because I would be stopping to reload the casing anyway. I will be upgrading to a 15lb horizontal unit in the near future though, as it is also easier for a one person to run since there is less leverage on your work table.
The 2 speed gear box is very important to me as it makes reloading much easier. Be careful not to use the high speed for stuffing on smaller stuffing tubes though, I stripped out the gear box on mine and had to replace it ($60.00 for the parts at waltons).
Matt