I carried an FN M16A4 everyday for several months. Shot it, slept with it, dragged it through mud, sand, water, muck, snow, etc. and never had any issues with reliability or accuracy. I would say go for it if that's what you really want as they're good rifles. The price tag seems steep to me considering you can get a teir 1 AR for less, but it sounds like you've fallen in love with the FN.
The guy who said he'd rather have an AR10 shouldnt really be considered into your decision process since the AR10 is a totally different beast (size, caliber).