I also got my 2020S today. Only had maybe 10-15 minutes with it so far. I got it for those times I don't feel like lugging around the huge board that has my Broughton SSDI on it. (Not that this is in any way a replacement for the SSDI, nor is it supposed to be, but so there would still be something on my smaller board to fatten and sweeten up my tone.)
For those purposes, and for auditioning it tonight, my chain was:
Passive J5 > Broughton Solarian > Empress bass comp > Broughton Fliptop or SVPre > 2020s > Broughton Messenger headphone amp, bypassing the EQ and H/LPF of the Messenger
After a short trial, I can say that the 2020S is very subtle, but very sweet. I had to go back and forth with and without it in my chain several times to figure out what it was doing, and I'm still not entirely sure I know what it's doing or how to best describe it. Keep in mind that this is through a headphone amp. I think you'd be even harder-pressed to put your finger on the difference if you're using an actual amp and cab. But I'm sure there would be a difference.
Whether or not I can adequately describe the difference with it in my chain, I can say this much: I like my tone better with it than without it. What I think I can nail down at this point is that it shaves off some highs and ultra lows, but in a very pleasant way. You might say it "tames" the highs. And that's with me using a couple of other things in my chain that already cut highs, and only running the tone knob on my bass about 50%. It just makes things sound sweeter. Especially when playing on the G string, and particularly up high on the G string. (This next part is subjective: Fuller? Warmer, maybe?). I think a "tone sweetener" is the best way to describe it. And if I run it after my preamp pedals and run them hot, it distorts ever so slightly in a very pleasant way.
So far I'd say it's a keeper, and it definitely makes me want to try the original 2020.