Audio Research PH5 Cartridge reccomendations

I'm seeking the opinions of others who have the PH5 or, perhaps, other tube phono stages. I recently got a PH5 to mate to my new VTL 6.5. I got it as a barely used demo. Even with lots of warm up, I felt distressed that the sound coming from My Linn LP12 and Clearaudio Virtuoso Wood cartridge was a bit too rolled off and not impressively dynamic at all.Yes, I did do the proper cartridge impedance matching.
After stretching my already stretched budget, I decided to replace the original ARC-supplied 6922 tubes (Sov Tech it seems with a set of NOS Mullard/British made 6922s from the early '60s. Wow! the difference was amazing and non subtle. After a day or two of break-in my phono section has a beautiful warm balance and dynamics up the wazoo.
My question is if anyone else has had a similar experience with tube rolling in the PH5. Also, among my concerns at first was that my Clearaudio cartridge may have been a poor match. With the original tubes, there was way too much gain in the PH5. I thought maybe the cartridge had too much output for that preamp. With the new tubes, the gain seems to be about 20% less and the music really blooms. All comments welcome.