@Bob Carnie - I've had very poor results with MGWT and Arista liquid. Maybe one good print out of 6. Seems to be a very short sweet spot where the developer is just-right. Most prints have that crazy mottled star-pattern mess. (Though I did find the fixer-explosion phenomenon to be present with Arista).
I've been assuming that LD-20 simply has a different formulation that works with MGWT. Planning on trying it next.
As for papers to try - recently there seemed to be a lot of Agfa MC 111 and 118 on eBay, even some 16x20. I find these very good and "legit" lith papers. Paper that exhibits 2 or 3 stops fog in standard dev still gives me snappy whites and clean borders with lith. The Agfa isn't amazing color-wise, sort of a muted yellow-tan, but it does take toners quite well. Brovira turns up a lot, it's more of deep blacks and cooler tones, but it has buttloads of silver and tones great too. As I recall, longer dev times. Any of the Maco (or other re-brands) "expo RF" (all the packages look the same, just different logos printed) are holy-grail warmtone papers (I've only EVER seen them 8x10 though), and like Ektalure and other classic warm papers, they just explode with Moersch Omega.
Ektalure simply rocks, but I find the drydown to go a full stop darker so it's difficult to print - when you see the slightest tones in the highs, it's done. And Ektalure (for me) is a one-time print - bleaching kills the unique color, even selenium turns those oranges more brown and murky. And a bleach/redev seems to really open up the grain of the paper and kill any smoothness.
The best, #1, most kickass thing I've found is going 2-tray for lith. Warm tray of dev, 2nd tray of warm water with a splash of old brown or very tiny bit of fresh dev. Once the print seems like it's getting close, go to the warm water and the critical snatch point slows down. You can go back to the straight dev if needed, since the paper now has some dilute dev in the emulsion, it takes a minute to speed back up. This has been a huge help for me to get "closer to perfect", and you can see the print much better in the dilute dev - the highlights are much easier to judge, and I feel like you get more delicate highs with more tonality this way.
16x20 Ektalure, 2-tray dev, no selenium or bleach or post-toning: