Towbar advice for a BMW X1

We are completely new to caravanning and have just ourchased our first caravan, a Swift Challenger 540 (2007).  I am looking around to work out the right towbar to get fitted to my 2014 BMW X1 Efficient Dynamics.  The van has al-ko stabiliser fitted and have deduced that we need a swan neck, and that the van has 2 pin electrics.  My question is this, should we go for universal electrics or if we go for dedicated (all fitted by a mobile fitter) will i then have to go to bmw to get software updated so that electrics work or is it better just to go for the universal?

Thank you.

Jen