I prefer the QS system to SQ. Pretty much all QS decoders are built the same because of the way Sansui held the patent. They all work, but have limitations. But at least you can HEAR a difference when you hit that QS button. Too bad there's maybe less than 50 total LP's in QS.

CD-4 is my favorite. After spending $400 on a Linear Contact stylus and cartridge that can handle 45,000hz.... and aligning everything. Geodiscs are WORTH the money. Now, my CD-4 system is super reliable. Love some of the Japan-only discs from the Stylistics or Hot Butter. Heck, even Van McCoy had a release in Japan. Indeed... I can do the Hustle in Quad.

SQ.... ugh. I have arguably the best SQ decoder they ever made and I'm still not convinced. Sure, it can make something spin around the room but when the recording gets really "busy", the whole soundstage collapses.

I prefer to stick to CD-4, tapes or SACD. I'm sure when I go for the big dirt nap it's either all going into the dump or a museum.