I prefer air cylinders cos when you close the doors you need a little over ride closing action in most of the cases, and a servo can't stand this.-

I adjust the air cylinder travel by inserting a piece of plastic or brass tube cutted to an specific length into the cylinder shaft.....I'm sure this is no new

Also prefer to hold the hinges with screws instead of glue.

Call me crazy....bud I do enjoy playing with door's hinging [&:]