Am seeking experience with early or vintage Gore Tex garments and other gear as to useful life of breath ability and waterproofness. I recently spent $2 at local thrift store on a Banana Equipment Goretex Parka with Iv-79 markings under GT label. The jacket is pristine. I also have a vintage REI GT parka in likewise great condition with removable down lining. I have no desire to return to Gore, but just enjoy these well made and durable garments.

I can’t answer your question, but I am envious. I had a Banana Equipment jacket like that in the late 70s and at the time, I didn’t know that had the best quality and design practicality in that style of jacket that I was ever going to see again. It’s degree of waterpoofness was never 100 percent, and that aspect got worse as the years went by, but that was due to the nature of Gore-Tex in those days. If I had the chance to buy another, I sure would.

I have an EMS Goretex snow shell jacket that finally got pretty wet after beating the hell out of it nearly year round for at least 7 years. I stayed with it until it got silly because it had hidden pockets and small touches that gradually got less present in anything but the most expensive ones. This is old enough to be the two layer stuff I expect.
I don’t feel that Goretex owes me anything on this jacket considering the hard use it got, and it is still fine for using as a shell on moderate temp dry days for snowshoeing. It just can’t go out in steady rain any more.

I still have an Early Winters Gore-Tex jacket bought in 1979. That was the first time I had seen GT used. The outer material is a tough Taslan nylon, the inner lining is a meshlike fabric bonded to the GT sandwiched between them (3-layer laminate). The jacket has big snapfront overflap over the zipper, high collar with a zip-off brimmed hood, huge pockets, and Velcro wrist adjustment. The cut is perfect for vigorous outdoor activities.

I wore it for winter bicycling, hiking, and occasionally for x-c skiing. It really lived up to its breathable yet waterproof claims and it STILL does. Its one downside is that the material is somewhat stiff and bulky when rolled up, unlike newer jackets. But that is because it is obviously sturdier material than many of the new GT jackets use. The feel is similar to that of my now-defunct Stohlquist GT drysuit and the Kokatat GT Meridian I replaced that with.

To keep water beading up on the outside, once in a while I treated it with DWR liquid specifically made for GT garments. I also use the same DWR liquid for an even older Woolrich 65/35 breathable anorak whose design I wish new garments would copy.