Both the thermaltake you picked and the H100 suggested are for cpu only. If you really want to w/c both cpu and the sli gpu's, you're going to need to design a custom loop which is way beyond the scope of this forum. If a loop is what you want, I suggest going to overclock.net in the w/c forum and asking in there. Those guys are all over custom loops.
If you want to water-cool the GPU's, you need to get into the realm of custom loops which are nowhere near as simple (and much more expensive) as that Thermaltake or a H100i.
If you want to water-cool the GPU's, you need to get into the realm of custom loops which are nowhere near as simple (and much more expensive) as that Thermaltake or a H100i.