There seems to be a dizzying amount of McMillan stocks available, and I'm sure each are best for different roles/needs. I've been trying to beg google to help me, but I still can't find a comprehensive source that will list the pros/cons of them all. I'm not in the immediate market for one, still saving up money for a Tac Ops or even a Badger M2008/AICS build if I like the stock. Seems like the A5 is the latest and greatest, and the cons seem to be centered around its weight... And apparently it's the updated version of the A4... But I'm willing to bet the A4 is still favored by some as it's still in production lol.