Great story.
I'm the same - been using my Kemper for 8 months now and at rehearsals the other day I took my beloved Marshall JMP1 preamp and hooked it up. I used to love the tones this unit gave so after rocking a few tunes with some Kemper profiles I wired the JMP up - expecting some of the old magic and BANG - masssive disappointment. Sound wasnt as clear, punch or 'big' as the Kemper.
In my mind technology has simply moved on and as much as my logical brain keeps thinking a great valve amp should beat this toaster into the ground - simply put it doesn't.
Looking forward to continuing my Kemper adventures