As it is a FR restriction, here is my personal list of super/hyper cars in GT5. I went off price and power.
Aston Martin
DB7 Vantage Coupe '00
DB9 Coupe '03
DB9 Coupe '06
V8 Vantage '99
Vanquish '04
Dodge
Viper ACR '08
Mercedes Benz
SLR McLaren '09
SLR McLaren '03
SLS AMG '10
Spyker
C8 Laviolette '01 (Listed as FR on GT5, think it's actually MR)
TVR
Cerbera Speed 12 '00
As you can see there isn't many, at all
So i went with borderline Sport/Super cars
BMW
M3 Coupe '07
M3 '04
Callaway
C12 '03
Chevrolet
Corvette Z06 (C5) '00
Corvette Z06 (C5) '04
Corvette Z06 (C6) '06
Corvette Z06 (C6) [RM] '06
Corvette ZR-1 (C6) '09
Corvette ZR-1 (C6) [RM] '09
Dodge
Viper GTS '99
Viper GTS '02
Viper GTS-R Concept '00
Viper SRT/10 '03
Viper SRT/10 Coupe '06
Mercedes Benz
SL500 (R129) '98
SL500 (R230) '02
SL600 (R129) '98
SL600 (R230) '04
SL55 AMG (R230) '02
Shelby
Series One Super Charged '03
TVR
Cerbera Speed 6 '97
T350C '03
Tamora '02
Tuscan Speed Six '00
Tuscan Speed Six [RM] '00
Looking at this list, you must remember. Most super and sports cars are mid engined, the RUFS are rear engined and the rest of the supercars are 4WD