I figured I should upgrade to WHS 2011 while it's still cheap and available. I was happy with the odl version, but really wanted to go higher than 3GB oif RAM. I really thought I'd miss drive extender, but it's big a non-issue, as Windows built-in software RAID is quite capable. I installed the OS on an old Intel G1 80GB SSD (which was tricky since it requires 160GB to install). Then used Microsoft's software RAID to mirror two 2TB drives (not identical), and created another RAID mirror across a mismatched 1TB and 500GB drive, and was able to format the remaining 500GB left over as a another unduplicated drive. Replacing a drive is easy enough - I just break the mirror, put in a new hard drive, and recreate the RAID. I lost the ability to have a single large hard drive, but I also can now choose which drives old which data, which I couldn't do with DE. Software RAID may not be the fastest, but it's very easy to use, and probably faster than DE (since that is also software-based). So the loss of Drive Extender is really not a big deal, there is enough flexibility in software RAID to get the same effect.