I just printed a bunch on the MGWT, MCC 110, and a little on Slavich as a control - all the same image, same tray. The Adox and MGWT BOTH got the spots something fierce, even in fresh, although dilute, developer. I increased the dilution and kept going with MGWT, and the spots went away, but so did the blacks and any semblance of lithy-ness. The Adox always had the spots, but was always able to get strong blacks (even went too far a few times, so I don't know that the dilution or weakness was the problem). The Slavich always gave a great print, no matter when it was pulled, except for a few exposure errors on my part (it is a much slower paper than the other two).
I think the spot pattern may just be the way the image forms on those papers. The Slavich has an even pattern (which works on EVERY neg I've tried), but the others have a sort of random fungusy cluster pattern. I think I might need to find a different image to try.