Gearbox is quite easy to use after about 10 mins practice
Motec can do boost control according to gear too

it also has traction control
You can always use a boost controller like a a turbosmart e boost 2 and adjust it manually via buttons.
I have my buttons mounted to my steering wheel now to select up and down if I feel the need to give it a bit more beans suddenly
Definately go sequential, you will not look back
A mild tuned 5cyl will see 300bhp for starters and will have loads of torque.
Great for a car that will weigh circa 550kg