[400TT]

It's quite common up here to have both fitted and that's what we have done on the Harrison. Use lap/sash belt for street and harness for racing. Just push the harness down the back of seat and down sides of seat when not in use...more tricky if your harness runs through the top of the seat.

Personally I wouldn't even think about using harness for street...it's just not suited for that sort of driving.