I've had a k1000 for more than 20-years. I've used it in the mountains in cold weather, and on the beach, actually wading well into the water to take photos of surfers. I used it to photograph sports when I worked for a newspaper. I gave it rough treatment and it worked well. I used everything from Kodachrome 25 to Tri-X.
Now, it's developed the only problem I've ever had with it - the light seal around the mirror is deterioriating and the mirror sticks up sometimes. It's an easy fix for a repairman - there are even kits sold on ebay.
I'd strongly recommend it as a camera for learning. And look for one of the metal ones.