F1 is a re-brand of Valeo. The same stuff you get if buying Valeo in the first place, just painted blue. I've noticed this same sort of funky resistance in the pedal throughout the stroke.....I've had a ClutchNet setup that was 10x worse. It was so bad that if I launched the car with really high rpms, the pedal would stay down and then kick my foot as it decided to come up. Zero modulation.....
I can't tell from your description if you're having the typical bleeding problems that happen in any clutch install, or if you're concerned about the way the pedal resistance builds and sorta goes away when it gets to about 1-2" from the floor. The piston on the slave cylinder isn't the most robust thing in the world. Almost every time I do the clutch on the RS, I need to go back through and bleed the system.
As for the slipping....this F1 stg 2 clutch I'm using now, seems a bit weaker than the last one I had (a couple years ago). I don't think they know what the exact parts are when they put a staged kit together. If they do, they certainly don't know how to accurately describe it. I can't go by whatever "% above stock" marketing jumble they dish out. I am at the point in usage where I need clamping force numbers that are used as a standard form of measurement. I like the price, and the fact that they don't actually build the stuff themselves......but I'd much rather peruse their stock myself to build a kit, then let them paint the pressure plate blue.
