I have a Stock tower. Fairly good but could be better. On the ash canister and on the main lid screws go into plastic and can easily be stripped. Also, when the plastic ages it cracks when the screws are tightened. As porerviously mentioned, the ash canister doesn't have a tight fit so the air can't be controlled as well as you would like and the "ears" can bend.
Today at Cabelas I looked at the new Stock tripod style with wheels (not a tower) that is similar to a Weber gold. It appeared they addressed all the issues mentioned above! Ash canister tight, air vent on lid nice and tight, screws not in plastic, etc. Its a nice grill!
They also had a Stock with table similar to a Weber performer. It was nice but the lid had permanent, punched air vent slits that can't be adjusted.
OK Joe Vertical Smoker, UDS, Komado Acorn, Weber Kettle Ranch, Weber Kettle, Stok Kettle