I have a Cary SLP-98L that I use with a Cary V12i (Siemens NOS EL-34s and 7308s). I like this set-up quite a bit. The Sylvania 6SN7Ws and cryoed GTBs combination in the preamp certainly doesn't hurt the sound quality and are a large improvement over the stock Chinese tubes.
However, I have always been interested in Joule-Electra and purchased an LA-200 preamp that Jud Barber upgraded to an LA-100 MkIII. It uses a 5751, 6550, and pairs of OA2s and 6EM7s. I have been quite impressed with this set-up as well, although the Joule is still breaking in. Right now the Cary sounds a bit more musical, but I suspect that will change over time as the Joule adjusts.
However, I have always been interested in Joule-Electra and purchased an LA-200 preamp that Jud Barber upgraded to an LA-100 MkIII. It uses a 5751, 6550, and pairs of OA2s and 6EM7s. I have been quite impressed with this set-up as well, although the Joule is still breaking in. Right now the Cary sounds a bit more musical, but I suspect that will change over time as the Joule adjusts.