Yes.... No problems.... : Lots of people have mounted them horizontally.
The calibration routine is exactly the same. Just follow the instructions and it will work. 99% of the reported problems have been due to failures to install drivers correctly or due to failures to follow the hardware calibration properly or due to failures to set MAME up properly to use them, followed by failures to calibrate the individual games in software.
As long as you take those steps properly it will work.
Best Regards,
Julian (Fozzy The Bear)