I am hoping these are good examples of:
1. Mid grade
2. Low perf
3. High perf

What I see that gives me that impression:

The first has a couple of chips and a lot of junk weight; nothing on the back. 7oz total
The second has a higher ratio of ICs, and is much lighter overall but also empty on the back side. 3oz
The third has chips front and back, and little else. The Al covered jacks have gold connectors. 2 oz

What is your opinion?

In my opinion all 3 look like Peripheral High Grade. Those big BGAs usually help the overall value. Then again, I could be wrong.

All are high peripheral

_________________
42 6F 61 72 64 73 6F 72 74 2E 63 6F 6D