What is the best all in one water cooling kit for 100-150 dollars
I'd say go with the NZXT Kraken if you're looking in that range. It's the one I plan on getting when I start pushing my FX8350. The Cosair H line are also generally highly recommended, but reading the reviews there are a few too many accounts of the system failing and ruining mobos for my liking.
If you can fit dual 140s then the Kraken X60. If you can fit dual 120s then the Corsair H100i.
If you are looking specifically for a dual 120mm then give some thought to waiting for the Swiftech H220. It is scheduled to hit the market at the end of February for $139 USD. Saw a pretty impressive demo video from CES. It is a higher price then the Corsair H series but it has a much more powerful and less noisy pump, and you have the option to expand it to cool multiple GPUs if you choose to in the future. If you need it now and can fit an X60 then go for it.
Agreed. Mega excited for swiftech to come in a kick Corsair's and NZXT's asses in the all-in-one water cooling department.
I know that is not the answer you are looking for, but any reason why you are not running a good air rig and buy a real DIY WC kit later? For example the XSPC RayStorm is a good staring point for CPU-only cooling and is not that much more expensive. Be sure to scrap the tubes that come with it and buy some PrimoChill Adv. series... the original tube is crap and prone to cracking.
http://www.frozencpu.com/cat/l3/g30/c321/s1310/list/p1/Liquid_Cooling-Water_Cooling_Kits_-_Brands-XSPC_Water_Cooling_Kits-Page1.html