We'll have to see until season 3 occurs. and if you don't like Duncan (I agree he is a little overrated) he'll probably be eliminated soon. The pattern so far has been
2 Grips, 2 Gaffers, 2 Grips, 2 Gaffers (probably Heather, then Duncan, not Harold or Leshawna since they didn't get as far in TDI as the other two), then 2 Grips (maybe Courtney since when one-half of a couple has been eliminated the other half is next)
I just speculating, though.