Don't waste your money on Sports Seats
As bad as the stock seats are in the X1, the Sports seats can feel even worse if you have big thighs. The Sports seat is exactly the same width as the stock seat, and only add the thigh extension, which doesn't help much because it is too narrow. But, the Sports seats feel even more narrow because of very rigid seat boltering meant to keep you in your seat in tight turning. Unless you are a stick figure, you will be in pain from the poorly upholstered bottom seat cushion side bolsters digging into your sides. After extensive test drives on both the stock and sports seats, I decided on the stock. Despite having purchased a new 2017 X1, I have to say that these are the worst seats I have ever sat in, in any car....especially in any BMW. Shame on BMW for cost-cutting the seating!
BTW, I am 6'1" and 230lbs