Welcome Mike , indeed a nice fleet of cars ! 840Ci and the SL 500 are great choices. I had two 944s, one of which was an S2 for a combined 20 years some of which overlapped with my two 968, one manual and one tiptronic. Other than looks they felt like two completely different cars from a driving perspective. Eventually I had both of them supercharged. I sold the tiptronic several years ago. So enjoy both of your new acquisitions with many miles and smiles ahead.
p.s. my wife was born in Slany ( near Kladno ), but moved to Prague as a young girl and lived there until she was 20. I've been to Czech Republic and Slovakia a few times , but not since 1976 ..so that's a loooong time ago :closedeyes: