I have has 2 MINIs with leatherette and I still have a 2001 325i with leather.

I've never been a fan of BMW's leather... and their leatherette weathers great and doesn'tget nearly as hot as leather in the sun.

That said, you can EASILY tell the different between the two.

If you want to actually use your BMW for some "fun" in teh sense of biking, camping, etc... definitely get the leatherette - it cleans tremendously easier.