Nice plants, its up to you..... your best bet buy a 20-30x hand microscope and look at the tricomes....... if they are a milky white color go for the harvest...... that means they are fully developed without starting to degrade and lose thc content...... Now as others said if you are going for sales give them 5-7 maybe even 10 more days and then harvest as they will put on weight..
Actually in second thought...... run a clean water flush though your plants for the next 5 days then harvest.... this will remove all the chem's and other stuff which can cause the smoke to not be as tasty and natural....... The flush has turned some of my shitty harvests into amazing ones
Sadly most people get to stoned and forget that part....