12AX7 tube for 122RD50 overdrive channel

With the 6l6GC-STR from TAD I found a very good sounding power-tube and I really like the sound they make. But with the Ruby Tubes 12AX7-C in the overdrive channel I�m not so satisfied. The gain is very weak and the tone is very brittle, something you don�t really need in a MM amp. Any suggestions for a tube with a good and smooth overdrive tone with some gain and low noise ?

I've found that on a stock RD 50, I like to reduce the gain to get the sound I like. I really like a 5751 (gain 70) in place of a 12AX7 (gain 100). I've also tried the following:
12AT7 (gain 60)- Not bad, but not quite enough gain.
12AU7 (gain 20)- Great sound, not enough gain
12DW7 (gain 20/100)- I like this a lot, 2nd to a 5751.
I've never used TAD tubes, but I have found few Chinese tubes that I like. I've used Ruby tubes, and I've never cared for them. I prefer Sylvania, phillips, RCA, GE, and JJ (depending on the tube type) for the preamp tube. I use Winged SED 6L6 for the power tubes.