For all the problems with the merc/mando class, I still love playing it. It is very dependent on group support, but the burst it can pour out from range is pretty sweet. Stealth scan works for covering VS doors and nodes without standing right on top of them although you still don't want to defend alone. I use Jet Boost/Concussion Charge quite often to knock people away from those, too. Having a good healer with you makes a lot of difference, but winning those 1v1 match ups against classes that should defeat you is pretty satisfying.