This thread has caused me to review my athletic shoe status.
I now rotate 4 pairs of running shoes, 4 pairs of hiking shoes/boots.
I ran for years in Asics Kayanos. I still have 2 pair of those, one pair of New balance 1080, and my newest pair is a doctor/ shoe store recommended Glycerine Brooks. I have only run on a treadmill with the Brooks, so they have a lot of miles left on them. They have quite a bit of cushion, and that's what I need to keep my knees and hips injury free. The other 3 pair have lost a lot of tread and cushion.
I just started running outside again, so my thought is to alternate between my current brooks and the 2 pairs of Asics. And order another pair of the brooks to keep inside for treadmill use for a while. And throw out the NB. Then as the Asics totally wear out within the next couple months, I'll rotate my new treadmill Brooks to outside use and buy a new pair for the inside. Maybe go back to the running shoe store for an updated fit/analysis.
I always rotate a new pair of running shoes into the mix on the treadmill for a while before putting into outside use.
For hiking, I have 2 pair of Merrell boots, 1 pair of Merrell shoes and 1 pair Altra Lone Peak 5. The Merrell's seem to last forever - hardly any tread wear. I've had several pair of Altra lone peaks (great shoe for easy flat summer hikes) and they are extremely comfortable, but tread wears out fast. My current pair of Lone Peaks has very little tread left, so I'll probably buy a pair soon.
The ultimate every day shoe for me is Merrell Jungle Moc. Slipon. I have 2 pairs - older pair for workshop, light yard work and walks around the neighborhood. Newer pair for casual.