Not real big on time per pound, but as a reference I did an 8 pounder on the UDS last weekend. Kept it between 300-350 and was done in around 6 hours, let it rest for another hour (I was pressed for time). I foiled it at 160-165 to help speed it up even more. The key, which I'm sure you've read before, is to wait till it probes like butter, or the bone pulls out easily. Obviously it happens at different times, but sometimes a rough example can be helpful. I prefer low and slow because I like the relaxing nature of the process...but hot and fast yielded equally good results.
Have another one on right now, going low and slow on this one though, hence the early morning start. Should probably head back to bed but the smokes got me wide awake.
Never thought of using a freezer bag before
I always assumed you need to use the Food Saver type bags. Good to know!