Having raced a bike engined car for a few seasons I find the sequential box has a few big advantages for me; the first is the speed which you can go up and down the box, there is the ease of use (up or back) and the clutchless shifts freeing up the left foot.

For road racing braking with your left foot is an advantage but there is also the left foot braking (rally technique). I often get asked how I manage such high corner speeds. While trail braking accounts for most of the corner entry, the last bit comes from preloading the throttle (after I'm done with the heel and toe downshift) preloading the throttle ever so slightly gets the rear of the car to squat without unloading the front. I manage this now but it's a lot easier to do with one foot on the brake and one on the gas.

End of the day while I can do whole double declutch heel toe downshifts all day long, I'd rather have the faster and easier sequential/bike transmission.

Tom