Where I'm driving sets my choice -
Track events, I choose to wear racing shoes - mine are Spimpson, I have both the hightop and lowtop versions. Only problem I have found is that the fabric portion of the shoe doesn't like water or damp grass, and over time will seperate from the sole. (Makes a nice air gap
)
If I'm just out for a short ride, then I slip into a pair of "slip-on" driving loafers; the kind that has the little rubber nubs on the bottom. They also don't like water as the whole shoe is more like a bedroom slipper (all leather).
Try to avoid shoes where the sole extends beyond the sides of the shoe, as this will surely catch on your other foot when using the pedals in such a small space (been there and done that)
I do the "deck shoe" thing every once in awhile (when just moving the car around or washing it). The grip is good, but the soles will catch sometimes.
Driving with flip flops anywhere in these cars in "Just Plain Crazy" in my opinion.
AND, NO Floor Mats on the Track!!!
TL