After having Johnny & Princess for a week, I felt they were acclimated enough to their new surroundings for me to give them an opportunity to leave their cage, if they so desired.
Just a side note, I put in a new 32 inch Bood Comfy Perch inside their cage. The smaller one I installed looped back to the adjacent wall and got droopy from their weight. So the 32″ perch helps support it by going perpendicular under and across from it. Johnny and Princess love it! They also use it as a walking bridge from the platform to the loopy perch, which is on the other end of the cage.
At any rate, on the day of their proposed excursion I opened the cage door open wide. Johnny and Princess were not interested. I did not want to pick them up as to alarm them so I simply left the cage open. Two hours later, they showed more interest in exploring the cage than leaving it.
Day after day, Johnny and Princess do not feel compelled to leave the comforts of their cage. Even when Fang is hanging out with them, all three feels more content with staying put.