The reasons I like to use the mejlik props:

1) Carbon fiber props don't need to have the prop bolts loosened when not in use to prevent crushing the prop hub due to swelling (this is a PITA).
I am in Texas and we get lots of humidity and dry air also. This may not be a problem in more northern locations.

2) The Mejlik props don't seem to load the engine as much, alowing for higher rpm with less load.

3) The carbon fiber props look GOOD!!! ( hey, why not??)