Does this guy you're talking to know anything about the 5th Gen LGT? What he told you is completely backwards. The one in the link on your post is the one you should get, for a direct drop in replacement ... no modifications at all. You will only need to set the proper spring back pressure, so the BOV will remain closed at idle, while the engine is pulling vacuum.
I have mine set-up as a BPV in the full recirc mode.