Chad, we have an early 20 series tractor that the GS2 works flawless in. SCV recording works perfect, right on the money.
On the other hand the late 20 series we have both the SCV and 3 point recording starts too late and stops too late for whatever reason I cannot figure out. Come to the end, raise plow it should stop recording when plow hits fully raised position. It doesn't. Turn will be halfway completed before recording stops.
As for fuel use monitoring, I haven't done a report yet after unloading data but on the display you can see an actual  task avg and the avg for only when recording is on.  This is on a 20 series tractor, 30's I think are different. Haven't ran a 30 series long enough yet to play with it.

You'll love the GS2 in the sprayer with swath control pro. i know I sure would not want to be without it!

Here is a shot of the GS2 in the 4930.

Sorry it's a little fuzzy. it's hard to take good pictures in the field at 20 mph while hitting foot deep pivot tracks.