In regard to the pins on the XT mount, I can assure you that they need protection and exercising by just pushing them in several times, usually accompanied by a squirt of ACF50, otherwise they stick in and the usual problems will occur.....
Had mine for some time, excellent unit with great connectivity and functionality and really bright.... so bright I run mine around 80%....
It can get a bit fussy on connections, but usually sorted out easily, it can depend on what you are connecting and in what order....
I still use my old 660 on the RT's mount as a backup, but man, it is so slow..... I simply will not pay the amount of money being asked for the BMW version of the Garmin, regardless of how well it works with the spinny wheel thing....
Recently while on my last IBA ride, the XT had a bit of a bender and needed switching off and on again... also, sometimes on a route, if I change the route slightly on the move, it keeps trying to send me back to the last missed waypoint, it should ask you if you want to skip it so I must have something set wrong..... on the move though, sorted by stopping the route then restarting at closest entry point....