Bought a pair of ECC35 tubes from Sergei. The were meticulously packed and they work wonderfully.
The shipping was a bit slow, but it was because of customs I believe. I've never experienced this before. Sergei was very helpful and reassured me that I would get my package. Everything worked out in the end and it wasn't too long of a wait. About two weeks from NL to USA.
He gets my full recommendation.