Nah, Nikwax is silicone based, as far as I know. It's a lot more environmentally friendly than Grangers or Storm, which are flourocarbon based treatments. You just have to use more of it as Flourocarbon proofings are more concentrated.
I'd totally forgotten that I'd started this thread, because it was a long time ago. Truthfully, I've become a little less impressed with the Storm proofing of my anorak. For a while, I was expecting the water to simply bead up like it does on my nylon based Entrant jacket. But it doesn't, at least not to the same degree.
When it starts to rain, and I'm wearing the anorak, the water beads, but then soaks in. This I'm not too worried about, as it allows Ventile to do exactly what it's supposed to do, swell, get stiff, and become highly water resistant. It also dries a bit faster than it used to, provided I'm wearing it. But...the proofing didn't really do what I expected it to do. It's not a big deal, I still stay dry. It just didn't do quite as much "beading" as I expected it to. Mind you, the proofing was VERY effective, but only for a short while. It's almost non-existant now.
I've even heat-treated it twice since I proofed it, and it doesn't make much of a difference. So, I'm at a bit of a loss for words, and a little embarassed at my excitement about proofings back when I started this thread. It seems that it worked wonders on my anorak for a while, but not anymore.
If someone wants to take a stab at this, I'd appreciate it.
Adam