Crane's and others, care to comment on a good preserver/water proofer that won't darken the color of the boots much? I have some obenauf's LP (for another boot) and some filson boot oil (courtesy of you guys). I did notice at least for my other boots that the LP darkened them up quite a bit, not sure I'd like to do that to the 1000 miles since I love their standard color so much. Is that just inevitable with water proofing or are there good neutral ones? Thanks, this...