GameShield

Does anyone have any feedback/comments about it?

I'm considering getting L.A. Noire, and it's listed as one of the two DRMs (the other being Rockstar Social Club).

From what I've mined off the Steam forums (too lazy to link; I closed the tab anyway), it's an install-limiter (per machine), except "under Rockstar policy", the limit is unknown (e.g. it can be 1 install or 100 installs, or whatever you want it to be).