with heavy auto-x/tracking the gr2s lasted me 3 years. they did the job, but good predictable tires would help much more. id say to spend the money from the struts into an extra few events if you have the time.
here is my car on gr2`s and whitelines. this is the sharp right at the end of the long straight at shannonville motorsports park. about 110km/h+ or so. pretty balanced, no complaints for the money spent.