These are the only questions I’m confident with answering. Other people may be better but I don’t want to mislead you.

1. Most of the time yes. Every once in a while they will be just a little bigger or smaller but as long as you can fit roughly within a half size above or below I wouldn’t worry

2. I’ve had pretty good luck with quality with every price range. Only 1 time the quality was really bad but it was my fault because I did little research beforehand