I don't know what you concluded about the 760is.  If you still plan to use it, please change your mind.  I used a very similar BigWater kit years ago; no single part of the system is very good which makes the whole system not very good.
 
As far as kits go, the XSPC Rasa kit is way better.  It has better components and is also a better base to upgrade off of.  You can add other blocks and radiators to the loop and the pump will do much better at keeping up.
 
But, if you are going to throw your video cards in the loop as well, you are going to have to do some serious upgrading on the radiator.  You will want either a 4x120mm or two 2x120mm radiators as a minimum if you are going to cool both your CPU and two video cards.  A single 3x120mm radiator would probably cut it in a pinch, but your CPU and video card temperatures probably wouldn't be nearly as low as you would want for the money spent and the overclocking headroom wouldn't be as high.
 
As far as memory goes, I am using this kit and I would recommend it (4GB):
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231444
 
It has nice tight timings, low voltage requirement, and pretty low cost.  G.Skill also has a good track record.
 
If you want 8GB, they sell a similar kit here for only a little more money:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231440
 
As far as PSUs go, I would recommend to go big.  You don't need a 1200W PSU now, but you will probably need it sooner or later when you decide to upgrade your GTX 460s.  I just figure that it is cheaper to buy a high output PSU now instead of adding up the cost of buying a lower output PSU now and then buying a higher output PSU later.  But that total depends on your personal upgrade cycle.
 
These two 1200W units are both highly rated and feature excellent performance and overall efficiency:
 
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371043
 
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139014
 
Otherwise, at a more sane price and power output for your present video card setup, I would recommend this PSU:
 
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139016
 
Still has similar great efficiency and modular cable system but in a lower wattage and lower priced package.
 
I would also recommend one of their TX series PSUs such as a TX850.  With the TX series, you are sacrificing efficiency and the modular cable system in favor of lower cost.  On the other hand, you can get a higher output TX PSU for roughly the same cost as a lower output AX PSU.  It all depends on whether cost is a big factor.