I think that's an "S" mate.
I'm more curious as to why one the VGT Mazdas is Gr 1. & the other isn't.
Looks like the standard car vs a detuned version for Gr. 1 - 710PP vs 653PP
(The original in GT6 has 717PP.)
It's shaping up as Gr. 1 cars having PP's around mid 600's and GR. 3 cars in the low 600's.
Regarding the '(S)'.
I note there are 2 versions of the VW VGT Roadster.
Both Gr. 3.
One with '(S)' has 613PP, the one without has 607PP.
I still can't workout what the (S) means.
And back to my earlier point regarding the VGT's.
I guess not all cars will be GR.1.
Some may just be left as they are.
A Chappy 2X with roughly 800PP, or the 2 top SRT's with roughly 850 and 950.
Can't see them being detuned to Gr. 1.
*Edit*
@Samus
I guess I'm prompting you to take a look at your master list regarding VGT's.
Now I know I haven't seen every single shot out there.
But I don't recall any Merc VGT shots - but you have named both versions.
I have seen both adjusted versions of the VW VGT - but you name 3.
Also, there are 2 Alpines and there are 3 Tomahawks.
And the Tomahawks - Dodge or SRT? (SRT in GT6)
You probably have reasons as to why you have listed them as you have, I'm just pointing out inconsistencies from my perspective. 👍