Hi,
Well, I can share my experience ...
Once I installed Windows XP (about a year ago

) on my new Western Digital 120Gb 8Mb cache hard drive. I formated it, with a single NTFS partition (I wanted 2 partitions, but I was going to change that latter).
After installing Windows XP, I installed Partition Magic 8, and re-partition to a 25Mb+94Mb both NTFS partitions (I don't remember if the numbers are correct, and I can't confirm them right now).
What I can tell you is that I had no problem at all, I played with PM8 for a while, to see what it could do, all the options included, etc ... and found no problem at all. I really liked the software.