oneways require a different driving style. You must be smooth, not use the brakes and be extremely consistent and focused, because the car has quite a lot more steering off-power, which makes it easier to hit the inside cones in the turns (and flip over...). Pretty much everybody will turn faster lap-per-lap times with one on carpet with rubbers, BUT not everybody will be faster over 5mns because of a higher mistake occurence...
At a higher competition level, pretty much everybody runs onewys on carpet with rubbers in Europe. My advice: if you can't do a perfect run with 2 diffs, don't try oneways. If you can run 5mns with each lap in the same 3 tenths of a second, then try one.
Recommended setup changes: a little less toe-out up front, and a stiffer suspension (both to tone down turn-in)
When the flag drops, the BS stops.
The train stops at the train station. The bus stops at the bus station. In my office I have a workstation.