Best is too subjective. I really love all the ones I've had. I don't use clean channels, so I'm more of a single channel guy that uses guitar volume for cleans, and then boosts a hard rock or dirty channel for metal stuff.
BE50 DLX: My first Friedman. Loved it. It started the journey.
Slax: Channel 2/JBE was my favorite on this amp. Didn't play the other two channels, so I flipped it.
BE100: I had a 2017. It was great. I was missing the Thump and Response knob from the BE50.
JJ100: My favorite. Took me a while to figure out how to run the EQ for my tastes, which was Presence up, Treble back. This was my gigging amp for almost 3 years. The only thing missing for me on this amp was a Thump & Response Knob. Mine already had a JBE MV knob.
Enter a custom mod JJ50 Dave did for me. The JJ circuit in 50w format, and added DLX features (no clean, just JJ BE & JBE). He added what was always missing for me with the JJ100.
Dave can do whatever you want if you want something modded.