Hi Christopher,
From all the reports I have seen I felt that the Pirelli's were they way forward, and that's what I had fitted. No regrets yet and I'm now 7500 miles further down the road. Reports I have seen suggest to expect approx 25000 miles on these, but who knows I may get more or less. Only time will tell!
If you look at my previous entries
you will see the history of my case. First DO NOT BE FOBBED OFF, insist that the wear is not satisfactory. Refer the dealership to James Bell at BMW UK. He is the customer service manager. I have spoken to him recently and he is well aware that there are a number of unhappy customers with this issue and he should engage with the dealership to resolve the problem, in fact, the dealerships should already be aware to look out for this now. However, expect to have to jump through all the hoops set before you. This is assuming that you kept the tyre pressures correct ( which of course you did!
you can argue this by the wear pattern i.e. different wear caused by under and over inflation). These will include a full KDS alignment check (BMW's fancy name for 4 wheel tracking check) expect to be presented with a bill approx £150, but get a quote first and an agreement that if this returns as OK then BMW pay. If this proves to be OK (don't let them tell you that the FRONT wheel alignment was out, this does not cause this wear issue on the REAR tyres) you will be asked to return the tyres to Goodyear for an inspection and report. IMPORTANT NOTE: You DO NOT have to do this via BMW, you can get your replacements from whomever you choose. They should return them to Goodyear free of charge (regardless of the outcome of the inspection). Check around for the cheapest price on the Pirelli's, surprisingly sometimes Kwik Fit do good deals ONLINE that take some beating.
Expect the inspection to take approx 8 weeks. If Goodyear agree that the wear is not normal they will refund you a percentage of the value in line with the amount of unused tread. There was no arguement in my case, from Goodyear and I know that at least one other forum member had the same result.
Document everything, and at the end (if you have a succesful outcome) complain to James Bell that you should not have to go through this rigmaroll, after all you bought the tyres with the car and so your contract is with BMW NOT Goodyear. It should be BMW's issue to resolve with their supplier.
It will take time, but stand your ground and you should be OK in the end.
Goodluck and keep us posted on your progress!