I've never run any tyre for longer than a month apart from Eagle F1's..! I used to use the GS-D2's back in the day and the newer version (GS-D3) is even better. They are excellent in the dry, and inspire confidence in the wet unlike any other tyre (standard Potenza's on my EP3 when I bought it scared me!). Only con to buying them is that they are a softer compound, so if you drive hard all the time, then don't expect much life out of the (I used to go through 3-4 front sets a year). As previously mentioned, they are discontinued, but some are still laying around, make sure you get the Y speed rated ones as they were the ones made in house in Germany, the W rated ones are from when they shipped production to Taiwan. HTH.