Here are my results
All voltages are measered on the motherboard, BIOS isn't always correct.
Everything you're going to see is 100% stable.
Stable = SuperPi 1M + mbench when loop 5 starts + CPU-Z launch together with mbench

667MHz CL3 . only 'important' voltages are mentioned & no screens
1.80v | 669MHz 3-4-3-4
1.86v | 667MHz 3-3-3-4
2.06v | 667MHz 3-3-2-4
2.26v | 667MHz 3-3-2-4

Now overclocking begins:
2.26v | 728MHz 3-3-2-4


2.26v | 806MHz 3-3-3-4


2.26v | 834MHz 3-4-4-8



2.13v | 1018MHz 4-4-4-4


2.26v | 1054MHz 4-4-4-4


Conclusion

This is unbelievably great cheap ram! I think this is the best price/performance available at this time.
It's just a pity I couldn't reach 1066MHz Cl4 yet, I'm still working on that.