I am starting to plan out my next computer build. Will running two SSD's in RAID 0 fetch me much of any improvement over a single SSD in Arma?
No. If you are doing a new build then RAM is the key
. Don't waste your money on SSD's. RAM is so cheap right now. 32GB or more.
This will be the same when ArmA 3 comes out. (It is the same engine.)
Set yourself a 25GB RAM drive and stream the entire game from there. NOTHING IS FASTER. PERIOD.
I run all of ArmA2, Operation Arrowhead, BAF, PMC, SimHQ mods, ShackHUD mod, and almost every island made for ArmA2 from my RAM drive. View Distance 10K, all other settings max. Never any slowness, LOD switching, loading....