I have been referring to the lexan D-ring which ArcTeryx identifies as the haul loop in my posts. Actually, when I first read it tested to 400 lbs, it struck me as a whole lot of weight, but I quickly dismissed it because it wasn't relevant to me, given the miniscule amount of weight I'd place there.

It's a good question to clarify.

I've found that the drop seat on these harnesses is pretty much impossible to use. The tab that the buckle goes into is too tight to easily release the buckle. Initially, I thought it was just my harness, but I checked out others, and they all seem to be that way. Even with the harness off, it's difficult to undo the buckle, with it on, I find it to be impossible.

I replaced the Arcteryx buckle with a Petzl buckle. Works much better. I can now drop the leg loops while wearing the harness.

I can't believe no one has mentioned the durability (or lack there of) - I have returned two of these because of what I would consider lack of quality construction - especially for the cost. Has anyone else had issues with this?

I think I tried to operate the drop seat once and found found it rather difficult. Adjusting the length of the leg loop straps (the rear ones, attached to the drop seat clip) is also a major pain, and virtually impossible to do yourself with the harness on (which, of course, is how you need to do it to get the length right).

I have not found the leg loops to be uncomfortable, nor have I had any problems with the gear loops. They are made to pop apart so that you can reverse them. Perhaps, the person (people?) who had problems with them falling apart got a defective unit on which they do not snap together correctly?

I also have never used the "haul loop" because it didn't look like it would hold the weight of a locking biner, let alone a rope.

Additionally, I have found the buckles on both the waist belt and the leg loops (I have the X-350a) to loosen gradually over time, and require periodic tightening. I have heard of other people having similar problems with other harnesses, but never had any such problem with my previous harness (sorry, can't remember the model or manufacturer right now).

That said, I love the harness. It takes up a small fraction of the space in a pack compared to my old harness, weighs next to nothing and is as comfortable as anything I've used. When trad climbing, I use ice clippers attached to the slots between the gear loops to rack nuts and tri-cams, and find that I can manage a pretty unreasonable large rack in a well-organized and easily accessible manner.

There are several kinks and opportunities for improvement, but none of them make me want to go back to my bulky old harness.

As to the durability issues, I've used my R-320 exclusively (likely between 70-100 days climbing)for the past 9 months and it still looks new. Have used the haul loop for tag/haul lines on multiple occasions and never have had issues. It is by far the best harness I have ever used when you take into account weight and bulk.