Pro tip for any BMW owners, MHD is a tuning company that makes great hardware for this.

Even if you're scared of tuning your engine, their dongle originally for that purpose is one of the fastest interfaces and supports Wifi.

The difference in speed is large enough I stopped needing a battery charger to flash my ECU and TCU (would still recommend one though since you are technically playing russian roulette doing that...)

Bonus: If you do care about tuning, they have some excellent off the shelf tunes to go with it