What is the likely weight of the shown version and the "racer" model?
With the racer model, what is the difference between your top and the GM one? (other than cosmetics, of course.)
Material? It looked a little like the skin was vinyl- I'd prefer fiberglass or plastic.
What is the window material? Plastic? Glass? Does it have a defroster?
Why do you have the huge overhang over the window between the buttresses? Is that structural (for the 2 piece design) or cosmetic? Have you done any aerodynamic testing?
What will the seam look like in practice? That white line in the pics only appears to mark where the split will be, and isn't an actual seam.
How easy will it be to remove the center section on it's own? How about the whole top?
Can the top be used without the section that attaches to the trunk lid?
I'm of course not expecting any rollover protection from a part like this, but how "sturdy" will it be if used in autocross, trackday, dragstrip or "fun driving" situations? I'm not interested if this thing will be popping out of place or cracking if the chassis flexes while approaching the limits of the car.
I really like the idea a hard top with trunk access, as I never wanted a convertible in the first place, but I didn't want to wait for the coupe to get my Mallett.
Overall it looks good, but I think that the "buttress" area and the overhang over the rear window still need some work. It's hard to say for sure without either one in front of me, but the GM top's buttresses seem to approach the middle of the car with a steeper angle, and slopes downward at the back.

It also slopes downward at the rear more, making the top look smaller. Your top is giving me a '32 Ford Coupe vibe because the top (seems to) go straight back instead of sloping downwards.
If you're finding that this shape significantly reduces drag, I'm for it, but if not I like the GM one better.
One more bonus puzzler: Is it possible that your design would be producable as a targa-top? I'm not saying I'd be interested in that, I'm just curious.