Falken is in the process of replacing its Azenis RT-215 with the new Azenis RT-615.
Among the ITR crowd, the older Azenis RT-215 has been regarded as an inexpensive, sticky tire for dry pavement and autocross use, with excellent dry traction and handling. However, it is also
very fast wearing, typically getting only about 2/3 as many miles as the stock Bridgestone RE010 (same tire, different size, same treadwear as the NSX OEM Bridgestone). And its large tread blocks make it much worse on wet pavement and in standing water than almost all other street tires. It has a tendency to lose grip when the tires get hot on the track.
The newer Azenis RT-615 is designed to do better on wet pavement than the RT-215, and to maintain its grip even when hot. Don't expect it to last any longer than the fast-wearing RT-215 (incidentally, part of the rapid wear is due to its shallow tread depth of 8/32" when new; most street tires are 10/32"). The RT-615 costs about 30 percent more than the RT-215 it replaces.
Both Azenis tires are excellent choices as an autocross tire, as well as a street tire for those who live in dry climates (e.g. Southern California, Texas) and don't mind replacing their tires frequently (although some would quip that category includes all NSX owners, by definition

).
gtr said:
Does the A022 grip better than the Azenis? I know the Azenis are very dangerous to drive when wet with 40% tread left. I'm serious considering the OEM, try this new 615's, or Azenis sport and appreciate everyone's opinion.
IMO, you really ought to try the OEM A022H tire. It offers crisper handling than just about anything else out there, including the Azenis.