Is there a baffle in the "doghouse" on top of the Spulen PCV plate? The VWR plate has one that more or less forces the oil to climb over it before it can flow to the CC. It would probably be an improvement to either design to have the hose fitting on top of the doghouse (exiting vertically) rather than in front...
I received my Spulen PCV plate today. There doesn't seem to be any baffle inside. Seems to blow straight through. I can't say if the design is the best or not, but in the case of the OEM, the issue is probably with the rubber flapper on top which actuates with vacuum and an internal spring against it rather than the baffle channels. In the case of the VWR, the top mechanism if you will may, may not be best. It's probably better for oil control, and maybe not as good in having a mechanical actuation to react with boost/vacuum fluctuations. I think that is where the OEM PCV fails.