Alright, after switching the internals back to the 716SA, I tested some more Riteks with PowerRec/AutoStrategy Off etc., but they just don't work well.

So next I tried a Daxon, which can be compared with 755UF burns here: http://club.cdfreaks.com/2004226-post205.html . Low speed yes, but I'd say my "716A/SA" did pretty well . PowerRec falls back to 8X with these in a simulation anyway.