I noticed something rather important missing in the realm of Full Disk Encryption, and that was benchmark data. The methodology I followed may be a bit unorthodox but would provide me with a consistant platform to test with.
I installed Windows XP SP2 on VMWare Fusion and applied all the patches available from our WSUS server. After installing the Benchmark application I created a SnapShot so that I could revert to the original install everytime with no deviations in installation, i.e. I was lazy.
I only encountered one major problem with running the Disk benchmark on PC Mark 04 when using TwoFish/RIPEMD160 encryption in TrueCrypt the entire benchmark would come up with the useless Windows Has Encountered a Problem message.
Unfortunately I could not get a trial copy of Utimaco‘s software. As soon as I can get one I will post an update.
Click Image for a larger copy
I did not expect to see such a large performance hit over unencrypted, even less so such a similarity in performance between TrueCrypt and PGP. Interestingly PGP had more of a hit on overall performance. Points of interest are the ALU and FPU scores, TrueCrypt AES being the least system intensive, and the fact that PGP has the best HDD performance.