Very nice set-up and results! Looking forward to the finish! :thumbs:
I would not recommend going by the pistils to determine maturity. If you're looking for amber, you will need a loupe or microscope to check the trichomes for color. The simpler method is to watch for the fans to die off.
When the fan leaves have completely died off and the sugar leaves are starting, the plant is ready to take.
(Special thanks to Muddy for this tip)