Hyundai and Kia have dealerships in Dumaguete, Honda regularly sends mechanics to Dumaguete to do maintenance on Honda cars.
Spare parts should thus not be a major problem for any of these three makes.
Getting a Honda in need of repair fixed might be problematic if the problem is urgent (because those guys from Cebu aren't here every week).
As for "servicing standards" (which I read as a "quality of work" enquiry), I can't answer that from personal experience. Among my neighbours and friends all three makes are driven, and I haven't heard any horror stories.