When the comp first starts the viscosity of the FDB is not as fluid, therefore your the head will bob up in down in a not too normal fashion...RAID is another issue.

MyDefrag also defragments metafiles - in fact the only thing all those applications can do with metafiles is to move normal files off the reserved area, and defragment MFT, making that area available for Windows only again.

You sure on that? Perfect Disk in particular moves and consolidates a bunch of metafile things to an area right after the MFT and pagefile. Those will be scattered over the drive prior to doing the boot-time thing and they end up in a nice contiguous block afterwards.