OK. Apologies in advance for the rant...!
About 18 months ago, I bought a pre-painted M Sport bumper for my 5er from them. It turned up, but wasn't the one that I had ordered (It was a pattern part rather than genuine). After several emails complaining, I eventually got a partial refund. My local bodyshop then fitted it to the car, but it was a really poor fit. To add insult to injury, the paint then started peeling after a week, as it hadn't been keyed in properly... so, I had to get it resprayed...
A month or so ago, I had some money in my Paypal account from selling some parts. As they took Paypal payments - stupidly - I gave them a second chance and ordered a pair of aero side skirts for the zed from them... They took the money, then told me that the price on their website was wrong, but if I sent another £100 or so, they could get the part for me... I cancelled the order. They eventually refunded my payment a couple of days later... It turns out that the price has been wrong for months and other forum members had the same issue...
I ended up buying the skirts from Soper BMW. They were able to take payment by Paypal... and the price was only a couple of quid more than the price with MStyle.
I wouldn't go near MStyle again if you paid me.