Hi and welcome to this forum.
Concerning the suspension question, dropping a NSX 10cm is a HUGE drop. Your car will practically scrape the road when doing that. Most people who lower the car lower it by 2-4 cm and that is quite a lot already. The standard TEIN settings is to lower the car 3 cm.
Lowering the car more will give you big problems on many/most speedbumps or driveways. Also, your tires will rub against the tire well when turning, your suspension travel will be limited and your suspension arms will not be horizontal anymore.
I'm awaiting delivery of my TEIN set but my current plan is to actually raise the car by about 1 cm (its lowered by 3cm now).
