I have an L1A1 (as [b]HiramRanger[/b] stated above, it's an inch-pattern FAL) and an M1A...and today (thanks to [b]GunnyG[/b]!), I tried an AR10 for the first time.
I liked it, but it's weird having a straight recoil path in .308. At least, for me, it's weird. I'm so used to my L1A1 that having all that directly under my ear/head is..strange. Not bad, just different. I don't know if I'd pick up an AR10. (I wouldn't turn a free one away though [;)])..mags are around $40/pop with rebuild kits, springs, followers, and bodies and all that...even 10 round mags cost an arm and a leg.
One thing I LOVED about [b]GunnyG[/b]'s AR10 though...it didn't heat up like my L1A1 does [:)] 40 rounds rapid-fire in my L1A1 and it's basically too hot to hold without a glove on.
My useless $0.02...