I've had several problems with my MMs over the past few weeks. Of the four that I have, two are cogging badly and I had a hard time flashing them. I emailed and called Castle and getting a response these days is like pulling teeth. It wasn't so long ago that you could call and get someone on the phone. I don't know what's wrong at Castle, but I'm gonna start going with Quarks soon. From my stand point, Castle is only hitting 50% with me.