i have seen so many threads about cables in the past. I would say without a doubt go with the one that everyone has had success with... the more expensive $100 one. I got mine from ebay if i recall correctly. Whatever the guides said to get.
It will save you money in the future when you go to pull codes or do your own work. Plus it lets you code your car if you would like.
2007 Alpine White E90 335i | JB4 | DCI | M-Tec Front and Rear Bumper | iDrive | Sport | Premium | Comfort Access | Heated Seats