You can still get around the metered air issue, it isnt a nessesity to use a vacum source. you simply bypass the pcv system and cap off the metered air sources. the one part i do have to agree with him on is the smell and vapors. in all of the cars ive used the system on i didnt have any issues with oil all over the engine bay. there is down sides to both styles of catch can system. if you run atmospheric you have to deal with the smell, and modding you pcv system. if you run with vacum, youll have to monitor the oil level in your catch can and empty it regularly. either way you go youll still help the oil issues. personally i always liked the cusco catch can. i just ended up modding the moroso one cause i was on a diy and do it cheap kick.