I have a pretty good stash of tube types that diverge from the typical numbers used in clones and kits. For example, I have plenty of 5755 high mu triodes and the Russian near-12AX7 equivalent 6N2P. I've also been collecting NOS octals like 12V6, 12SL7 and 12SN7 for years, as well as the 6L6-like 6P3S-E. The project I'm building now is mostly "by the book," but if I build more guitar amps, that won't be the case. I understand the issue of finding replacements on the road, but it's not terribly expensive to keep spares of these tubes around. Anyone else around here find it useful (or at least interesting) to build with "non-standard" tube types?