I'm looking to do something similar to my runner, so definitely keep us updated with what you go with and how it works out.  From what I've read, most people are fairly impressed with the OME set up, but the flex is not all that great.  I think that it's designed to be an all around replacement for the stock springs, but not necessarily for maximum flex.  Also curious if those are FJ80 wheels that you're running?  I like em.