I love all the older hydros. Some of my favorites to troubleshoot are Esco, Rotary, South eastern, Dover solid state, DMC, MCE, Westinghouse. I enjoy LRVS but usually have to fight my frustration.

Absolutely hate Kone, not as a company but from an electrical print standpoint. I have a serious lack of understanding how to troubleshoot the 831 and the other models that use a million input output boards. Haha

I've been making most of my progress on the schindler 330A's they can be fun to troubleshoot at times.