The best bang for the buck is to get this Mushkin DDR2 1000 RAMhttp://www.newegg.com/Product/Product.aspx?Item=N82E16820146755
and overclock it to 1066 with those timings. You should be able to overclock it without a problem, but of course with overclocking your mileage will vary
. Anyway the best brands are Mushkin and Corsair. As for the best bang for the buck, then it's whatever is cheaper. Of course with RAM you generally get what you pay for.