Zalman Reserator 1 Plus + Nvidia xyz???

I have a Zalman Reserator 1 Plus with an AMD X2 4400 and an old Nvidia 6600GTS card.

Originally I was planning to add another card hoping I could water cool both. At the time there were also some writings about the Zalman not being able to cool the high end cards (can't locate those articles now of
course ). But finding one of those old cards that would be compatible with what I have is too much of a drag.

Which means I want to pop in a 8600GTS or even 8800GTS as a pure replacement. Now, anyone having the old reserator running with a card like that? My current setup doesn't go above 50C. I'll just risk it with a 8600 but if I have moderate chances with a 8800 I'd probably go for that.

Facts? Opinions?

Eskimo