Well, the SCAR is basically a heavily modified FNC, and from my understanding they didn't change the internal mechanical parts much, so reliability shouldn't be much of an issue.
BTW, can you mount a 40mm grenade launcher, PEQ-2A (IR aiming laser/spotlight), ACOG, or CCO on the FAL without adding anything to it? And how fast can you change the barrel length?
I'm not sure I really see the need for the folding stock, but I guess SOCOM wanted it. Collapsable would be plenty good enough for me, and probably savce a little wieght in the process.