If the car is put on a setup board and well dialled in, I would guess 2.5 to 3 hours of racing on a set of sorex 24 in stock is do-able, maybe more but as time passes, you will notice the compromise on grip and lap times. with the 24 I found them to drop off quite slowly, unlike some other tyres.
maybe 28s are better in mod if you are looking for a longer lasting tyre on a budget
Air gap too can also play a part in tyre wear, as can the type of carpet, to a certain degree, but compound will always be the main factor.
I found the cs22 used to overheat and go off very quickly, they were too soft for any carpet track, too much corner speed kills the sidewalls....