interestingly enough I just got off the phone with Kokotat as I'm in the process of getting a replacement suit so I can comment a bit about their sizing and suits and I did own a NRS a few years back.
So, my kokotat (a front entry with some mods: suspenders and shoulder pocket) is about 5 years old. I just did a clean, dwr recoat, and new gaskets before a month long trip this summer. During the wash, with the suit inside out I noticed an area near the neck that appeared to be a delam but didn't have time to send it in before the trip so I just kept my fingers crossed. I was initially pleased that the dwr seemed to be working with water beading up, I was able to dunk fully for cooling in the hot conditions without getting wet. But as the trip progressed I was getting wet after swims and decided to send it in for a warranty evaluation and or leak test. Warranty eval is free, if it'd pass that I'd get charged for a leak test and repairs. Word came back that there was a delam and that
"... the suit was in good enough shape that they could warranty it" I emphasize that because it's a point where they have to make a judgement which might seem unfair if you're on the wrong side of that decision.
As far as sizing goes, my warrantied suit was a medium but when I followed the custom measurement process on kokotats web site
https://kokatat.com/custom/gore-tex-front-entry-dry-suit-dsugfeconfig it recommended a large suit with -3" on sleeves and -1" on inseam. Because my old suit mostly fit fine ( a bit tight going over my head) and a custom size is non returnable I decided to stick with medium. If I were near a knowledgeable shop like Kayak Acadamy who could help do the measurements and ensure me I'd like the resulting fit I might have gone full custom but on my own I stuck with what I knew worked.
They told me it'll be three weeks to build the suit so in one month I'll be sporting a brand new replacement suit so I'm stoked. I asked their rep how many suits end up getting warrantied for delams and he said less than 1%.
My experience with NRS was previous to buying kokotat I had bought an NRS model with a WP breathable fabric that was supposed to be just as waterproof and much more breathable. At that point I thought a drysuit would be a sweatbox and wanted that breathability. The suit had an overskirt and zipper cover that seemed a poor design, often being in a pain when donning. It also had a single shoulder pocket that was basically design like a jacket pocket; a zippered slit through the fabric with a inner "bag" that formed the actual pocket. This makes for a less useful design than what kokotat does; a pleated pcoket sewn to the outside of the suit. Also NRS suspenders were klunky with big plastic fastex buckle whereas K's are just velcro-ed straps and sewn loops; much better in my opinion. The end result of my NRS "experiment" was a return to purchaser (REI) after about a years use due to it no longer being waterproof. At the time employee's at Alder Creek told me to expect 2-3 years out of any non goretex suit and 5-8 of a kokotat goretex suit.
So for me the fit and function of their suits as well as the warranty makes me a happy kokotat customer and it'd take a lot to change my mind on that. On the other hand , when I was having problems iwith my first suit, I remember hearing somewhere that NRS will totally stand behind their gear and will replace suits even beyond warranty period if the user isn't happy. I don't know if this is true but the implication was that they were still a paddler owned business rather than corporate money makers and would ensure satisfaction. Not sure if that is true but might be worth asking if your friend has inside access as possibly implied by the discounts you mentioned.
