Anyone using Glowroot with ColdFusion or Lucee ?

I’ve not used it but was curious, based on your question. I just added it to one of my dev boxes running CF 2018. I’m impressed. I am very impressed.

Agree, it does look interesting. FWIW, FusionReactor (not free) has been doing well for us, so we're unlikely to change, unless Glowroot has big advantages over it, which I didn't see in a quick look.