CV joint bolts for vanagons/busses are the normal allen head type. Many other
VW's have multi point (12?) bolts that are almost the same size. They are more
of less interchangable as long as they are the same length. Close enough so that
if you don't look close you might use the hex driver and wind up stripping the
multi point bolt. Both types are high strength bolts and should never be swaped
out for a weaker bolt.

They should be torqued to the correct value, no more, no less.

CV noises. Many hear clicking/snapping sounds during certain driving situations.
Others will feel vibrations. The single best thing that can be done for CV's is
just to take them out and clean/lube them. Be sure to use the right grease too.
Moly-Disulfide.