I bought one of Anthony's latest barrel clamps and it is the best I have use yet. It actually has screws that allow you to tighten the clamp down on the shroud and tank. It does away with the inconsistency that the Avenger has had from the flexing of the shroud. My Avenger is now a full time one ragged hold rifle rather than once in a while.
I also bought one of his chassis kits and am in the process of mounting it. The parts are finished really well and he uses good hardware. A single page set of instructions is included but, if you need help, he answers his email quickly.
I for one will be glad to get rid of that cheap plastic stock.