I have many of these puzzle cubes that I designed from a class I took last year, and when I printed them in class, I really enjoyed solving my puzzles. A few months later, to now, I now have my own 3d Printer, and this is my second favorite thing to make! (Flexi's and Articulated things are my number one!) I prefer printing them all at one time, because you can start the print at the beginning of the day and end it at the end. Enjoy!
Resolution depends on how good you want it to look. The lower the resolution, the tighter and smoother the fit.
Enjoy solving the puzzle!