I have been wearing the pilgrim since its development days. I had friend in the UK who sent me a pair his unit was trying out and it was love at first ruck march. Basically they were looking for something as comfortable as the Spider but could hold up to the demands of special operations, specifically the ability to support moderate military loads. The Pilgrim does this brilliantly! It's a little stiffer than the Spider but just as comfortable and brilliant when you add those moderate loads. I have worn these in a very wide variety of environments to include military training and operations, light mountaineering, law enforcement, construction and more. I'm wearing a pair right now on a construction site in Kansas. They were fantastic when I was using them doing rope access construction in Seattle! Basically, any time I need something a little stiffer than the Spider, out come the Pilgrims.
A couple notes given some of the other reviews I have seen and my overall experience:
1. There is a goretex version and a non-goretex version. I love both and wear them in the appropriate environments.
2. Quality Control: With one and only one exception, the Pilgrim has been as bulletproof as the Spider. I did have a pair 2 years ago where the stitching came apart within 2 weeks of wearing them. This was the only instance of a Quality Control problem I have ever seen with AKU in 13 years and I have never seen another one since.
3. Durability: The Pilgrim is every bit as durable as the Spider, which in my experience has been legendary. The only reason I go through Pilgrims faster than Spiders is because I now work in construction and the abuse I subject them to is frankly insane and unreasonable. The kicker is that I wear Pilgrims in construction because I cannot find another boot for less than $700 that is both insanely comfortable and will last longer than a couple months. I can wear a pair of pilgrims for 4 years before I have to replace it. The average work boot lasts less than 4 MONTHS for me. So yeah, they're rugged as ****.
I could go on but you get the idea. These are boots I can't live without and wholeheartedly endorse.