For current owners with a coolbox - how well does it work? I've heard it only works while the rear A/C unit is on. Does it keep drinks REALLY cold, or just so-so cold?

 

It does not get drinks really cold. Basically it diverts your A/C into the cooler. Once you shut your car off it no longer refreshes the air inside the cooler so it is only really handy on longer trips or if you want to keep so cold drinks cold. I was surprised by how cool the drinks would be when needed. Of course this is from my 01 LS. I just got my 07 so it may even perform better.