I have never worn Kenetreks or Lowas, only Danners. Personally, I can't stand insulated boots unless it is really cold out. I have had several pairs of Danner's, but the only good pair was the first I ever bought. They were the old, uninsulated Danner Contractors (similar to what the Rainforest are now, but a little lighter). Wore 'em for work and play for eleven years. Foot always stayed warm and dry and they were as comfortable as a pair of your best slippers.
Someone might have already mentioned this, but Danner has a recrafting department for stitch down boots. I finally decided the old Contractors finally needed some refreshing, so I sent them off for the fullblown recraft - $150 for pretty much new everything except the leather. I know that seems like a lot of money, but what is it worth to keep a pair of boots that haven't given you a blister in hundreds (maybe thousands) of miles? When I gotta 'em back, they looked like new, just already broke in. However, the right heel counter they put in had a sharp edge that rubbed my ankle. I was pissed so I called up the recraft department and told them about it and the fact that I was leaving on a hunting trip in 8 days. They emailed me a free shipping label and said to send them in. Four days later, the UPS man dropped a brand new pair of Rainforests on the front porch. They said the couldn't get to them in time so they just sent me new boots. Good service, but not exactly what I wanted. Now you guys got me wondering if these Rainforest will be worth a damn.