When I got my SLX in 1985 it was already a little out-dated. The 6006 was on the market and my 1974 Modern Photography magazine (that I still have) had a test report of the SLX. The plan was to use the SLX well and when it breaks to get the newer camera. Well, I'm still waiting for the SLX to break. I must have got one of the good ones, it is still going strong.
Anyway I wanted to upgrade to the newer camera while 120 film is still available! (I'm still pissed that 220 B&W is gone)

I was a little concerned my older non-PQ lenses may not work based on some wording in the manual. However, but they work both in Aperture-Preferred and Shutter-Preferred modes (where as on the SLX there is only Shutter-Preferred automation.) Manual mode is a little funky because when you press the button to stop-down-meter it won't continuously read the aperture as you change it. You have to re-press the meter button after each change in speed or aperture. Makes it a little harder to zero the meter markings. Basically you zero in on the exposure by trial-and-error.

Both my SLX 90degree and 45degree prisms fit just fine, showing the focus screen and the metering information. My SLX electronic releases worked fine.