Is there that much of a difference in stiffness of a hardtop vs moonroof car?

I love having the moonroof but my next car is going to be fast and used for racing.

Which would you rather have and why?

 

I currently have a moonroof car and I track it... The only thing I have noticed is you get dimples on the top of the a pillar from body flex, they are not super noticeable but you can tell the metal has flexed. I fixed them and put a cage in, no further problems.

 

Other issue if you are some what tall is head clearance with helmet.

 

Define: racing

Is that just tracking the car in general Driving Events (HPDE's), or real NASA/SCCA door-to-door racing? Once you put a rollbar or cage in the car, it won't matter. The main issue is just head clearance with a helmet.

 

Mahjik's right on the money. I autocross my 7, and also do lapping days at my local track, and head clearance is my only concern. I have an R1, so no sunroof, and even then I get some rubbing on the headliner with my helmet. You might be able to solve height issues with an aftermarket seat and rails that drop the driving position down a bit.

You're probably going to put a roll bar in at least anyway, so i wouldn't worry about flex. Just head clearance.