Svetlana vs. Electro Harmonix 6L6G tubes

Curious if anybody has experience with both of these brands of 6L6G tube. I am going to replace the tubes in my amp and am curious what other 'gon members think. Thanks.
My favorite 6L6 to date is a Russian variant - 6N3C. What amp are you retubing?
I attempted to retube from the Svets to the EH for my GT SE-40. However, the EH tubes had a quality control problem that my dealer thought was caused in shipping. Went through 4 (out of 6) tubes in four months. Dealer gave me a full refund and I went back to the Svets. I believe that the EH produced more gain, but the overall sound was not that different. If you do go EH, make sure your dealer has a liberal refund policy. I also have a set of the Sovtek 5881s, and I prefer the Svets as they appear to provide a more robust bass.