
I've mostly played around with the EF86, making two triode-connected EF86 preamps. Very detailed sound, yet not overly harsh or bright. I'm building a new one (once the metal work gets in) for someone else using onboard regulation, chokes, etc...
I've also become interested in the EF40, EF12 and want to start using them. I also had some good sound out of a SE 300B amp using an SV83/EL84 - that was a budget version of a Loesch design.