R888, RA1, NT01 all use the same rubber compound. Carcas is different.
NT01>RA1>R888 on the '95M3 I raced in BMW club racing. I raced it in IStock and then, after I blew the motor, moved to JP w/a 2.8 (iron block) up front. 3175lbs dry in Istock to 2990 wet w/driver in JP. NT01's were best. I always ran my fastest laps as the tires corded unless I'd grossly overheated them (turn very blue). NT01s need far less camber to be effective than the RA1s.
'11 E90 M3, Mebourne/Black/Fox Red/Black, 6MT, roof, PP2, heated seats, moonroof, split folding rear seats, iPod/USB adapter -- 8/8/11 euro delivery! Technic harness, JL XD 6/600.