IMHO, the 800 and 900 MPL's are the shadiest... 600 loop, it depends on which side of the road and which part of the loop.
If you are traveling in a motorhome, and get placed in the 600 loop, and are backed up the the main road, especially in the front portion of the loop, then the name, "Sunny Sage Way" is all true. You will get hit with morning sun shining through the windshield which generates a lot of heat inside the coach. If you are in a trailer, then not so much...
The 1100 loop is not so bad shade wise...