Until recently I've been a VTL MB-125 owner with tremendous satisfaction. It uses EL-34's (4 per mono bloc)and I've used both JJ's and Electro Harmonics with no troubles at all. I used them for over 6 years and averaged about 30-50 hours a week. Never a reliability issue. I would check the bias every month or so and they almost never drifted or needed much adjustment at all. Be sure you never switch between tetrode/triode with it on, of course, but other than that they are just outstanding products with awesome sound [and superb] reliability. I hope your ST-85 has finally "settled down". Best of luck.
Reliability issues with VTL amps/pre-amps
I have a VTL ST-85 which I use mostly, in the triode mode. The left channel tubes have blown 5 times in a two year period. I had repairs and the tube compliment replaced by VTL during this time. After all the shipping costs, VTL replaced the last set of tubes for free and all is fine for now, but I'm worried it will blow again. No one at VTL has ever told me why they keep blowing. Has anyone had similar experiences with VTL? Is this type of problem common with their products?