Has anyone tried any of the coke-bottle style 6L6's made in China by Sino? I see them on eBay, going for $12-15 dollars a quad.

I'm working on a Bogen PA-to-JTM45 coversion, and want some tubes to stick in it for development & debugging. No sense blowing up nice tubes. I'll put in some nice KT66's once I'm sure it's right.

So, how are these Sino's for the money?