hifilover1979
Bigger than you...
I think some cheap tyres are worse than others so you may get lucky depending on what you choose. I certainly don't think it's a given that all cheap tyres are crap but I definitely have had a couple of really bad ones in the past ('Accelera' I think were pretty terrible in the wet and ice on my old Accord). Our Pug 107 still has the cheap Chinese tyres that it came with as they haven't needed changing yet and tbh they've given me no reason to worry at all, but it's no sports car obvs .
Accelera Phi - unbelievably shit; beyond shit IMO - as bad as Linglong (or you won't live long) tyres
I looked at a couple of 730Ds local to me when I was looking for my next 7 series this time last year; both had Accelera tyres fitted, in 20" sizes... I saw them, laughed and walked away!
If the owner of a car like a 730D only fits tyres like that; you can almost guarantee he/she has skimped on everything else on that car too