These came standard on the car (BMW M135i) and whilst they are lauded for their dry grip in the cold and wet they simply crap. Not cheap, budget tyre 'crap' but for a UHP top-o-the-range tyre they should be a lot, lot better.
In the dry and warm they grip like a vice, you can feel every notch on the road and know exactly what is going on a every corner, the only down side to these levels of grip is that there's no progression towards the point where they let go, aside from that they do a superb job in the dry and warm temps, eg above 12-15 degrees.
However, none of that matters in the UK much especially where I live (Scotland) as I need a tyre that perform well in the wet and these simply do not. They have low levels of lateral grip in the wet and break-away under power quite easily. Straight line performance is adequate but there's limited fun in a straight line !!!!
Unfortunately, given the UK climate these will be replaced this summer (2016) for either GY F1s 3s and Hankook S1 Evo 2s. I'll happily trade 10-15% dry performance for a 50% increase in wet weather performance.
Also, in the 225-40-18 88Y (from on BMW) the manufacturers recommended pressure results in excessive outer edge wear, so have to run 4psi higher to combat. Plus, quite a few M135i owners have experienced significant splitting and cracking on outer edges after only 1-2 years of driving... all-in-all, not a good show from the MPSS.