I called Samsung today and they said the 830 series is backward compatible for both SATA I and II. However, you obviously will take performance hits to the speed at which your machine can handle.
The support person went onto say that Samsung does not officially support the drives for Mac. People use them and they work, but Samsung only puts out software to support PC users. So he just warned about that. Regardless, I have seen plenty of successful reviews from people using the 830 drives in their Macs.
He also said that it is only necessary to buy the bare drive, not the notebook install kit. Since Macs use screws to hold the drives in place, it is not necessary to use a spacer. So save a few bucks and just get the drive and some sort of external enclosure for the old drive.
After this conversation, I feel confident that I could buy the Samsung 830 128GB and be happy. However, I am still wondering if the Crucial m4 128GB would be a better fit. They seem to be more open about their backward compatibility and working with Macs. Any ideas/suggestions?
Thanks,
RJ