Sizing: Description is correct about being long in the body. I wear a 42 jacket but took a chance and ordered one size up. Should have ordered my "correct" size. I have hot water washed and dried twice in an attempt to shrink the sleeves with modest success.
Quality: I have several WPG Aertex products and the JG's all feel softer than the Khaki versions except this one. It seems to be a sturdier Aertex material than the others which for me isn't a bad thing considering it's a jacket not a shirt. No issues with too small button holes or loose buttons. Definitely well made!
Overall: Despite the length which was explained in the description, I still give it a 5. Order your normal size if wearing with undershirt or regular shirt. Mine will accommodate both and the WPG British Jumper as well without feeling restrictive. Will probably order another in proper size and use this one for late fall layering.

Ed - Virginia United States

Im 1.81m =5'11 and 80 kg i have size 40 is perfekt. Great Shirt/jacket

Helge - Germany

I am really happy with the construction and fit. The fabric is quality and the construction matches the originals I have seen pretty closely.

Irwin - US