I have a 30 and can do a batch of 6.5 pound snack sticks with some room left. There are 4 racks, and I can get 3 mallards on a rack. I think with bigger chubs, like summer sausage, you could do 10 pounds no problem. I have used mine for several years now and am satisfied with it. Most of my batches are 5 to 6 pounds. I definitely recommend an AMPS smoke generator though to have consistent steady smoke. I’m smoking for myself and a few friends; if you are smoking for a bunch of folks then more room would be convenient.
I wish I would have asked that question more than 10 years ago when I bought my MES 30!!!
I didn't like cutting my Rib Racks down, or my Briskets, but most of all I hated it when I mixed a 10 pound batch of Unstuffed Beef Sticks, and I couldn't get them all in on my top 3 racks.
So less than a Year later I got my first MES 40!!