I use a 50/50, which I love. Very punchy.
Studio pre settings:
Vol 5
Mast 5
Treb 8.5
Bass 2.5
Mid 2
LD 7.5
'verb 0 (I use external FX)
LM 3.5
EQ
80 Top line
240 just above mid line
750 cut all the way
2200 right at mid line
6600 just above mid line
I REALLY tried to not cut all the mids, but any amount sounds bad to me. The toe setings are a bit of a compromise between the rhythm and lead settings, and are closer to the lead settings.
The tweeking was tricky. The PSA recto patch has a really punchy low end that I think is a combination of lows and highs, kind of like the AJFA kick drum with a 4kHz click added to the thump. Then I had to get some fizz, but be careful to limit it to just audible, so 6600 was tricky. The thing that the recto (and PSA) has, that I really can't quite get yet, is a bit of buzz. I'm not so much trying to get a recto sound as interested in whether I can or not. When I started, the big difference was that the PSA had a HUGE low end that was not mushy, and my previous attempts at that with the SP made me just give up and dial it out. Now I have a very good low end from the SP. The big difference now is that the PSA gets really high cut, so it sounds weak in the high end, while the SP has as much high end as I want. It also has a really alive sparkly response, where the PSA is more dead.
Overall my experience is that you have to kill off most of the lows and mids pre-distortion and ad them back with the EQ down the line. The SP distortion circuit really chokes on low frequencies. I got that cue from some of the guys who posted settings on youtube. In the end I tried to mimic a lot of their settings, but never quite got what I wanted. The EQ is very powerful, so a tiny change is really audible, and one frequency band in the wrong positions screws the whole thing up. I originally started with everything in the middle, trying to boost/cut to get what I wanted. What worked better for me was to drop everything to full cut, and add each band one at a time.