I've never had the pleasure of using Forte papers, so I don't have a point of comparison with Argentone. I bought a pack of 25 8x10 from 8 Elm and I've made a few lith prints.
So far, it has shown the most dramatic lith effect I've seen, bearing in mind that I am brand new to this lith printing thing. Very strong infectious development, starting for me at about 10mins.
I've been using the Moersch SE5 kit. I found the blacks to be extremely grainy and gritty with soft highlights. Very lith-y but I'm not entirely pleased with the effect. Wet colour of the untoned print was a soft beige-brown, with black blacks. Selenium toning at 1:3 produced a very interesting purple-black tone at about 5 mins that dried down to a browner sort of purple colour.
I was having a major problem with the edges of the print developing far more rapidly than the centre. After some thought, I imagine that's because I was using 8x10 trays for 8x10 prints and I was over-agitating the edge areas. Next time I'll move up a size in tray to see what happens.
You can see the effect I got with the two attached images, but the colour is of course different in the physical prints.