I have now read that your limit is 400 dollars . My suggestion to you is to get a pair of 400-500 dollar iem (variations, dunu Sa6 are good ones) that you can return/sell with ease, and a/b them with your app2.

Ps Check this list to help your choiceprecog’s. I agree with most of his grades and grading system. Just be warned that 1-2 grades of difference are not much.