If you're going to pay that price, check out Kakadu, Dale of Norway, Bemidji Woolen Mills or Pendleton. I think all of them make superior rugged outdoor clothing to Filson's.
I don't know about the others, but I can compare Filson directly to Dale and Pendleton, and I respectfully disagree.
I have two Dale of Norway sweaters, one is the SLC Olympics sweater, the other I purchased a few years before that. They are both very good, much superior to other virgin wool sweaters I've owned through the years. But comparing the yarns of either to the Filson Guide Sweater yarns, they don't come close. The Filson yarns are both twisted tighter and woven tighter, they thus have a significantly harder, more durable finish. The Filson also looks like the individual wool fibers are longer than the either of the Dales. Over the years, the Dale yarn fibers have loosened (kind of like climbing rope fraying a bit) and even pilled in a couple of places. Not significant pilling, just a little in the higher-wear areas, but I don't even have to look close to see the loosening and fuzzing of the yarn fibers. The Filson hasn't.
I have a 25 year old Pendleton wool shirt that I bought new, and a Sir Pendleton shirt I just bought new 2 years ago. I assume the Sir Pendleton is their top of the line, most highly worcested wool shirt. It is very nice. Both shirts are good, but the Filson shirts have finer wool fibers, spun more tightly into finer wool threads. The fabric feels softer because of the finer threads and the finish seems tighter because the threads are finer and there are more threads per inch. Because of the better weave, the Filson wool has a better "hand".
I'll agree that the Filson clothes are not as stylish. They are cut boxy, squarish, and look like they came straight from the 1940s or even the turn of the last century, but there is no question in my mind that when it comes to the fabric, construction, and individual fibers, they have a distinguishable edge.
One thing I would like to see in Filson is a lined Mackinaw cruiser. The Mackinaw is rough enough that I won't wear sweaters underneath. It's fine for wearing with vests and wool shirts and I've not had problems with either, but I'm cautious of abrading a sweater under a cruiser. I'm guessing the reason they don't is that a liner would wear out much faster than the coat itself and thus become the "weak link" in their durability. Still, I'd welcome it.