We are big Star Wars fans and are planning to get to DHS in the afternoon on a Saturday. Should I get FPP for Star Tours or wait in line? How much of the great queue will we miss if we do FPP?

The queue is nice, but I wouldn’t worry about missing it.

When we were there during Spring Break we FPPed Star Rours twice.
First time we met up with stand by at the exact same point - by that I mean the lines inside the building were the same length. Can’t remember posted SB wait time. No benefit.
The second time we used it the posted SB wait time was 60mins. The FPP queue reached all the way past the Indy merchandise carts! However we were told that the line would move quickly & once we got in the wait time would only be a few minutes compared to the 60 min SB wait… Wrong! Took 15 mins to get to FPP scanner, then once we got inside the FPP queue was longer than the SB! Although both were only a few mins wait, we’d waited longer outside to get to the scanner than if we had just walked into the SB line.
Maybe we were just unlucky but we won’t be wasting a FPP on Star Tours again in a hurry.