There are unlimited ways to plumb catch cans and some are much better than those ways you linked. Personally I would never vent a can to atmosphere, or drain the oil back, but each design has its merits I guess.
If you have oil filling the can you have much bigger issues, they should only be used to control the oil vapour and stop it lowering your combustion octane, or to stop oil condensation in the cooler and manifold imo.