About the size and measurement, you should buy the jacket based on your true body size. If you usually wear 36 then you should buy size 36. Don't size up unless you have big belly. The only part that the jacket won't fit you based on true size is the waist part. For your info, Schott 641 and Schott 641HH are same size and have smaller waist compared to Schott 141. I am not sure why Schott always recommends their customers to size up one size. Maybe they have more American customers who have larger belly when compared to Asian. I have a flat stomach and true size fit me perfectly. Leather jacket suppose to follow the right size and get them tight but comfortable.
Another aspect to look at is the finishing on the jacket. The naked cowhide has no finish, dull in appearance and a more pliable feel to the leather. The steerhide has a finish applied to the leather leather will have a slight shine and a more firmer hand. The horsehide has a very shiny finish and a very rigid/stiff hand to the leather. About the weight, the horsehide jacket is lighter then compared to both cowhide version. The thickness of the leather seems same to me. It could be due to lining weight as the horsehide version is nylon based while the zip out liner is wool based.
I personally like the horsehide (Schott 641HH) as its more comfortable and I like the shiny finish. You will look better too in front of camera and it creates nice silhouette. If you want a beautiful break in jacket, I would advise to choose either Schott 641HH or 141. The naked cowhide tend to break in more beautifully when compared to steerhide version.
Schott 141 front. Naked cowhide.
Schott 141 back.
Schott 641HH horse hide.
Schott 641 horsehide labeling details.
Cool jacket with nice silhouette.
All version comes with same type of zipper.
Nice out fit. This picture show breakin Schott 141 naked cowhide jacket.
Picture of Schott 641 from Rakuten. Japanese online store. You can get many nice cutting version from Japanese market if you are slim.
Details of Schott 641 steerhide.
This is how it look like if you are wearing Schott 641HH. Do notice the shiny appearance.
Schott 641HH horsehide black colour looks darker when compared to the other two schott jackets.
Me in Schott 141 cowhide. You can see that the jacket breakin nicely and follow my body shape.