CSC Vitamin Q capacitors good/bad?

[jonusgrumby]

I'm in the final stages of assembly of a push pull 300B triode amplifier. There are only two capacitors in the signal path. They are the coupling capacitors to the 300B grids. I use a high voltage driver and -90 volts on the 300B fixed bias, so the capacitors need to be 630 volts minimum. I have 0.47 uF 1000V CSC vitamin Q capacitors that I have planned to use in this amp. I've read a lot of good about vitamin Q caps, and some bad. I have had them for quite a while.

I used Sprague 715P capacitors in the breadboard, and they worked fine. The Jantzen silver series look promising too, but I have not tried them.

I want to stay away from metalized film because of the possibility of a short, so I am really only looking for a film/foil. I need a value of 0.47 uF to .68 uF. I'd like to stay under @25 US / cap.

Any recommendations or experience with the CSC parts?