Not necessarily - if you have the Quest car mount with its ciggie-lighter power adaptor, you can remove the connector and lead from the mount itself with a tiny torx driver. You can then attach the power lead to the RAM Quest mount with the same tiny torx screw (in fact the RAM mount used to come with the correct size torx bit). Buy an adaptor from HG or similar to convert the BMW accessory output socket to a ciggie-lighter socket. Plug in the power adaptor and away you go