My first pair of Hi-Tec Altitude IVs lasted around 10 years. I used them for work and for casual wear, and even hiked into Montana mountains on an overnight pack trip several years ago. They wore very well, and so I bought a new pair last year. The new pair has higher ankle support and seems a little heavier than the first pair, but are comfortable and appear to be durable. I did notice some sewing differences and that the tongues on the new pair do not catch pant cuffs, so that's a bonus. I recommend.