Managed to get some assembly and basing done last night:
Black Cat Bases not-Claptrap from Borderlands.
Better detail of the objective market one, now undercoated (black and then over-sprayed white).
The Brain-in-a-jar-on-tracks - bit of a bugger to assemble, slightly miscast. The jar and lid are loose for painting.The not-Left 4 Dead Hunters. I do like these, quite menacing I think!
Overall, a nice bunch of figures. Casting is fairly mediocre though - lots of moldlines on the robots, which took a good bit of filing. They're all undercoated now, in the same way as the objective marker Claptrap - black as a base with a slight white overspray - the same way I've done the rest of my zombies and survivors for the post-zomb-apoc games.