I used Core365's official chart for men's sizing. Measuring myself, I was able to get a perfect size without trying on first. It's a little stinky (new plastic) but that is starting to dissipate. Holy features batman! this thing has a lot of utility.
Surprisingly, although basic, this jacket can be easily styled and looks pretty great considering the price. It definitely doesn't look as cheap as it is. Imagine "high-end" cheap products, if that makes sense. Everything here was done economically, but done well. I have a feeling this jacket will last me for quite a long time, especially considering the ripstop.
If I were to criticize this jacket, the only thing I could say is be mindful of the sleeve length. Does not seem to be measured the same way as a long sleeve button up for example. The sleeves are a bit long, but there is an elastic, so at least it doesn't look goofy. To be fair, this style jacket it does make sense to have slightly longer sleeves (to avoid rain)