They look good! I have 5 GG autos going right now as well. They are 24 days old. I will say from day 15 up until now they grew really fast. Probably will triple in size on you in the next 10 days. I also have a slow one in my bunch. Since you are growing these I’ll share some pics so you can see the GGs as they progress.
Day 15 (just FIMed them all)
Its like topping, but you take a little less off and it can give you 3 to 4 tops instead of only 2 when topping.
Oh and the rule that says topping= 2 more stalks and fimming= 4 stalks is untrue , different strains react differently to each. My Olympia auto was topped and looking at the base stem you’d swear it had 4 -6 main stalks because each took on the growing boost of the main stalk and thickened up A LOT.