Gimsons will give you more than enough power. Conker couldn't push Satanix purely because Conker had nothing to get underneath. Satanix has a wedge, and so it lifted Conker up, reducing its grip and thus disabling much of its drive.

4 Gimsons, perhaps overvolted, will make for a plenty powerful featherweight. Tormenta ran four 12v drills at 18v with 100mm wheels. Thing did 10mph and it had boatloads of push.

It's as much in the design as it is in the power of the motors on paper.

Remember that bigger motors often require bigger ESCs and bigger batteries = more money spent later down the line. You could run 4 Gimsons with 2 Electronize 30a ESCs and a single NiMH. Perfectly adequate for a first featherweight, and perfectly powerful.