Here is the 60 page install and troubleshooting manual for the Bosch heater.
http://tinyurl.com/4fkecql
No big deal for a Master Plumber, but I would be curious if the RV repair tech's would have the training to figure it out, if something goes wrong. A guy would probably OK if you were staying where it was installed, the installer should have the resources to get it going if there is a problem. On the road, it could be a problem.
It looked to me that they have designed it for an RV, so most of the problems they had in the past on the original units should be fixed.
I know in Europe they have been used for a very long time.