I've been using one of these for a few weeks with my Mate2. Suction cup mounted to the windshield. I've bounced over potholes, rail road tracks, uneven driveway entrances. NOTHING has knocked it loose. I use a very thin case on the back, and simply lay the metal piece that comes with it, between the case & back cover. Does not bother the signal level either. No more looking down at my phone, or having it jet off into the floorboard if you have to stomp on the brakes. Some might consider .95 (U.S.) expensive, but it was worth it to me.
http://www.amazon.com/Bracketron-Si-...rds=Bracketron
http://www.amazon.com/Bracketron-Si-...rds=Bracketron
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