I just ordered a Springfield Socom II with the Troy system. I prefer a multi-position stock over a side folder. The side folders seem to offer more rigidity.
I thought I'd revisit this thread, since I am now planning on buying an Vltor Modstock (the E-mod version) for my M1A. This is a part of my ongoing mission to effectively and comfortably mount an ACOG on this rifle.
I know I had previously said that all the after-market stocks for the M1A are too heavy, but this is not true for the Vltor. I guess I just lumped it in with the Sage EBR and the Troy MCS without actually looking into it. The Vltor is just a GI fiberglass stock, with the rear end cut off and a machined aluminum adapter bolted on that an AR buffer tube and pistol grip attach to. It is actually a hair lighter than a regular GI stock... it also retains plenty of storage (even more than the GI M-14 stock actually).
After looking into it, I have decided that it is the way to go. I will post up how it works.