My 15 Rem 29er is still at 140, and I use the bike for rugged trail riding. No park or true enduro stuff.
That said, more travel might be nice, but I would personally hate to lift the bike up beyond stock for my application, since it already is a fairly high BB by current standards (and I run in the low position.
Not sure if I could notice a 10 mm change, but 20 mm would be very noticeable.