I've been considering the same cooler myself. Can power steering fluid be too cool? I would not think so. I don't recall my steering feeling heavy at -30º starts in Summit County. Maybe my synthetic ATF is more cold temp friendly?
Speski OffRoad LTD, Cargo Solutions for Toyota 4x4's http://www.SpeskiOffRoad.com
"80 series, with a fridge"
1976 FJ40, Project with little progress.
2004 Starcraft 10RT