Silenx ripping off Zalman much? Perhaps they're just having Zalman's contracted factory making their cooler for them as well - not exactly the same but very similar to the vf700 al/cu.
IMHO (not having either an 8800 [yet] or competing coolers), the S1 is better, and assuming you can fit one if will outperform all but maybe an actively cooled HR-03. It's certainly got price on it's side ($17.75 @ Ewiz). Lots of surface area, cools quite well passively (assuming good case cooling to start), cools better with a decent low-speed 120mm [or two - no need really for high-speed fans btw]. The only real drawback is the already noted crappy TIM on the ramsinks - easily enough to remedy as noted a few places. When I installed my cooler on the soon to be retired 7900, at most 1/2 actually stuck - but then again I didn't properly CLEAN the memory ICs before hand w/ 91% [?] Rubbing Alkyhol - in other words DO IT; may make a BIG difference! Besides, you'll need at least 10-12 (right?) to properly cover the 8800GT, and it only is supplied w/ 8, so more a-shopping you will go - ~$13 for the copper Enzotech's @ Petra's seems like a good deal.
IMHO (not having either an 8800 [yet] or competing coolers), the S1 is better, and assuming you can fit one if will outperform all but maybe an actively cooled HR-03. It's certainly got price on it's side ($17.75 @ Ewiz). Lots of surface area, cools quite well passively (assuming good case cooling to start), cools better with a decent low-speed 120mm [or two - no need really for high-speed fans btw]. The only real drawback is the already noted crappy TIM on the ramsinks - easily enough to remedy as noted a few places. When I installed my cooler on the soon to be retired 7900, at most 1/2 actually stuck - but then again I didn't properly CLEAN the memory ICs before hand w/ 91% [?] Rubbing Alkyhol - in other words DO IT; may make a BIG difference! Besides, you'll need at least 10-12 (right?) to properly cover the 8800GT, and it only is supplied w/ 8, so more a-shopping you will go - ~$13 for the copper Enzotech's @ Petra's seems like a good deal.