The best advice for choosing the right size for raw jeans is to stick with the raw measurements and ignore the difference between raw and one-wash version.They are the exact same jeans with the same amount of cotton used and end up in similar size after you wear them for a while.
One wash starts at smaller measurements but they expand more than raw ones and end up in similar after all.So, the only difference is whether you want to enjoy the unwashed raw feeling in the beginning or yo u rather chose to skip the soak.
I noticed repeat customers start to realize that the jeans expand quite a lot over time (after several months) and they chose smaller size, whereas first timers tend to pick larger size. Repeat users target perfect fit at several months later when the jeans faded well and expanded well. First timers on the other hand target perfect fit at the start and usually end up using a belt when the fade gets nice.
If you want to target perfect fit at post fade, you should bare the uncomfortable months of wearing the jeans for the first several months (barely buttoned up and you cannot even sit during these months)If you don't like to go through this uncomfortable period, you should look at the one-wash measurements and find your size.
Anyways, it's up to your preference.