Are they any decent in melee? Can you reinforce squad members by returning to the HQ? I'm asking this because they can't reinforce like the rest of the infantry.
like any other Elite units you just need to park them next to a base building and they will recover by themselves
They are very decent in melee.
Problem is for them to get there, they are more guardians of your back lines then frontal attackers.
Put them in the Trukk, launch them and some nobz, boyz, or Gorgutz himself into the enemy back line. If you do Gorgutz, then have him W to block projectiles, and send out the barrier ability from your nobz. Watch shooters melt, particularly heavy weapons squads.