Greetings!

As one of the obsessed, I performed my encoding with my standard audio set: full quality VBR using a now defunct tool called Siren by Sonic Foundry. Depending on your encoder, watch your track breaks carefully - you will want to have plenty of breaks if you are on a short drive, and the ability to fast forward or use bookmarks to set your position easily. VBR is much tougher to do this with.

Which version did you get? I would strongly recommend the UK version over the US version (for English language use). Stephen Fry is (in my opinion) better at the characterization than Jim Dale, and the original UK vocabulary seems more appropriate.