It really depends on one's body shape. I have broad-ish shoulders so sizing down isn't an option, but I can wear my field jacket with just a shirt underneath. (Though a light sweater is better b/c it fills the body.)
YMMV, as usual.
Sorry, I can't say as the field jacket is the only Eidos piece I own. Your best bet is to ask Greg and Kyle.My guess is you should take your normal size. Eidos is not as trim as LBM. It has bigger shoulders but is normal-sized otherwise.
Look at the measurements for Eidos's suits and sportcoats on the NMWA. If you think their jackets will fit you, then the field jacket should fit you as well, even without layering. It has a trim cut without being too slim.I'm 5'6", 138 lbs and it fits me nicely. It's not meant for beefier men. Perhaps @NickPollica can help with this sizing confusion?
Having just read Dieworkwear's blog post on cashmere sweaters, I say give the man some money so he can compare plies (e.g., 2 vs. 4) and brands (e.g., William Lockie vs. ESK) by wearing the clothes and visiting factories. It would be investigative sartorial reporting.
Strange. I also ordered the Eidos field coat in my suit size (US 38S/IT 48S). It fits me perfectly with a light sweater. I think I can fit a sport coat underneath but it's probably more comfortable not to. (A thick knit would work better.) The length is just enough to cover my rear.
Also, the coat is very soft and doesn't look as full IRL to me as it does in the pics here. It fits like an unstructured sportcoat on me.
This is my first Eidos piece. Do the Eidos suits...