Just tried on the KUIU that arrived today. Thought I might give you a run down if you are thinking of ordering.
First I am 5'9'' and about 190 right now. For comparison the Sitka gear 90% pants and jacket fit me just about perfect in large. Roomy enough to wear a thick vest under the jacket. Pants were roomy also.
KUIU
Merino:
I got all 4 merino layers in Large, pants in neutral, tops in camo. They are all high quality and fit well. The lighter merino is not scratchy at all, the heavier a little scratchy.
Pants: I got 34 and they are true to size, I can wear both merinos under them and they will fit better when I lose a few lbs. Pants are very high quality, the fabric is tough but stretchy, kind of a cross betwee the Sitka 90% and the lighter Sitka pants in thickness, but tougher. Good button front and good pockets.
Guide jacket in Large: Cut a little long past the waist particularly in the back which is good and a little long in the sleeves which looks like it has an area where you could have them altered if you need to. Fine for me. It is a bit snug in the shoulders and upper arms and although I can wear both merinos under it I would be unable to wear a vest until I lose some more weight. It is slimmer than the Sitka 90% large jacket. It is cut slim through the arms with no velcro closures which I like. May have to return it for an extra large and have the sleeves altered. The hood is very nice. This jacket looks as if it will break the wind better than the sitka 90%.
Merino beannie; Very light weight, stretches well.
Merino neck gaitor: Very light weight, stretchy for pulling up over your face for camo.
KUIU beannie: I have a big head and although the Sitka beannie fit me perfect this one is way too small and does not stretch very much, I would think it might fit a 7&1/4 or so. Got to send it back.
This gear is top notch and I think you will like it if you get a good fit. It is an athletic fit and if I weighed what I should I think it would be about perfect.