I did them today (after 8 sets of squats)
I did 4 sets of Goodmornings. My lower back felt very tight so I didn't go all the way down. I only went up to 135. I used to go way heavier. But with the tightness in my lower back; I was very cautious. I tried to stay on my heels. But even with lightweights and a partial range of motion, I felt my hamstrings getting activated.
If anything; they are a nice break from Deadlifts while still using free weights.