The USGA conforming rules at http://www.usga.org/equipment/conformance/Conforming-Club---Ball-Lists/
Just something that I want to do in the remote chance that I might want to enter a tournament where it stipulates conformance. I realize that many older clubs are grandfathered in (to 2024 or something) unless a local board or agency requires conformance, but even so I still want any new clubs I get to be in conformance.
Any that you buy from any major manufacturer from the last 5 years will be conforming for any competition you could possibly want to play in, for much longer than you'll ever own the clubs.
Buy the newest, latest, and greatest if that's what you want. But unless you're trying to convince your wife to let you buy new instead of used, the "I want to be conforming" argument doesn't hold water.
If it's the wife thing, I absolutely understand!