Need advice for upgrading memory

Mushkin and Corsair are both good names if your an enthusiast I'd go with somthing that has a faster speed and lower latencey than conventional DDR3 Memory. Ex: 1600 Mhz and 7 Cas Latencey is ideal.

Any of those you have up there are super choices.

To be brutally honest, I would just pick which ever one was cheaper.

All the DDR2 RAMs you listed are almost equal in performance. Just choose one of those which don't need EPP to be enabled to function in the highest clock (e.g. 1066MHz) and go for the cheapest one from the list. I am a sufferer of buying 2x2GB RAM which need EPP to be enabled for functioning@1066MHz.

Thank you very much for your replies!
I've got corsair memory and very satisfied with its performance. Within less than half an hour i succesffully set them to 1100mhz and cpu @3.9ghz. The system was stable for 7 hours and then i needed to go to work. I want to play more with advanced timings- now they are all on auto and will stress test the system at weekend for 15-17 hours to be sure everything ok.

If you want you can check my pc's video on you tube -
http://www.youtube.com/watch?v=zLyMq4mkPt0