The problem with Redline is, as you pointed out, pretty expensive and also not readily available as other options. Will be interested to see how you go though, haven't heard anyone else using Redline Engine Oil in their VR4.
I would have to say that redline is easier to get hold of than amsoil. Redline is stocked by Sprints, Motor traders and a few places online (in Aus www.performancelub.com) that are a bit cheaper