Gold Loop takes market from 30th and turns on 34th. From there it goes to HUP, CHOP, WOODS building, CRB & BRB. From there it goes to 38th and turns on walnut then turns on 42nd(?) Then to Presby. From there it goes back to 30th, down market.

The green shoots straight up Market to 38th and loops into presby. From there it takes 40th street to spruce. Then it goes to 38th and spruce, then to the VA. From there it goes BRB&CRB, WOODS building, the pavilion (also for HUP/PCAM). Then it takes 33rd to market them back to 30th.

Tl;dr: gold takes you to HUP/CHOP faster. If you're going straight to Presby, take the green. Alternatively, if you're going to Presby you can take the El to 40th and walk back a block