Combination Safe. This was very well thought out. For me it did require some post print cleanup to work though. I had to sand some pieces that were a bit too tight, and I had to work on the inside of the "top" with a razor knife just a bit. But it assembled very easily once prepped, and works nicely.
Next time I would probably try to print at .1mm resolution. Took me about 8 hrs to print all the pieces.