Which hip belt pocket? Brand? Xpac or Dyneema? GG? Zimmerbuilt? MLD?

Dyneema will be far more durable than Xpack, but a lot more expensive as well.

Waterproofness of either probably depends on coatings/laminates, seam sealing/taping, and the choice of zippers. Below is a quote from McHales website with relevant info regarding waterproofness of Dyneema.

"Dyneema and Spectra are essentially the same thing with Spectra being the USA tradename for the fibers from Allied Chemical that make up the fabrics. Most of our suppliers have switched to using Spectra and at the same time have stopped coating it, so we are using Spectra fabrics with various laminates to create the waterproof side. Dyneema is the product name for the fibers of the European company DSM."

AFAIK, Chris Zimmer doesn't build his pockets out of pure dyneema fabric. He's using dyneemaX (210 grid stop). Go with Xpac if you want higher water resistance. Personally, I'd go with cuben for full-waterproofness, but if you have any qualms about durability and your own ability to baby gear, then go with xpac.

I bet Chris Zimmer will make you Dyneema ones if you ask nicely and pay a little extra. +1 on his quality and service, you really cannot go wrong with Zimmerbuilt.

I'm going with a zimmerbuilt pocket….b/c he offered to customize it 2" wide (instead of 1.5) at no charge. The Dyneema X, cuben, and xpac are all the same price. The only thing I'm still debating is Xpac vs. Dyneema.

http://www.zimmerbuilt.com/hip-belt-pockets.html

From my research it sounds like the xpac material may be more waterproof than dyneema (one laminate) b/c it has multiple laminated layers, but I'm not sure of its durability vs. dyneema.

The awkward shaped and sometimes sharp objects that will be put in it don't seem conducive to cuben (fly boxes, forceps, knives etc.).

Hi,
+1 for Zimmerbuilt. I got his hipbelt pocket and shoulder pocket to use on my
Ion/Newt and they hold great after a year of use. I use hipbelt pocket chinched to my
belt loops even on non hiking pants to keep my car keys, credit card, pocket money etc.
Mans purse:)..And Chris is fantastic guy to work with.

Regards

I realize I'm late to the game on this discussion but still wanted to throw a couple of comments out there.

Another option for hip belt pockets besides those already identified is Zpacks. They're actually quite large and will hold a lot of stuff (internal volume of ~1 liter per pocket). Much larger than the pockets founds on my ULA packs or the Gossamer Gear pockets my brother has on his pack. I use them for some trips on my HMG Porter when I want to have various things easily accessible.

Cuben pockets can be pretty durable. There's lots of different thicknesses and versions of cuben. Something like the 2.92 oz/sq yd hybrid cuben is super tough but still really light for something small like hip belt pockets. Very weatherproof too.

Zimmerbuilt makes nice products too, so you won't go wrong ordering from him either.