We can share our experiences here.
My initial reason for hanging was to gain an understanding of the optimum vacuum chamber configuration for effectively handling the most amount of weight. I was testing up to 35 lbs for brief moments until the inevitable injury occurred… thrombosis of the vein just behind the glans. Scary to look at and left to wonder if it was permanent. Upside, I instantly gained 1/2″ in flaccid girth behind the glans :), which took a couple of months of rest to recover :(. That was about 18 months ago.
Fast forward. I have been on a formal and dedicated routine for the past 2.75 months. I am currently hanging 10 lbs for 40 minutes twice daily. I have had a couple of minor set-backs due to improper wrapping technique in the beginning and more recently an over-ambitious jump to 12 lbs which required a few days rest and resetting to 9 lbs for 1x daily sessions of shorter duration for a week or so to re-stabilize.
I have gained 1/4″ erect length with an often very significant increase in the flaccid hang.
Be consistent with your routine. Keep a detailed log book as it will help keep you motivated and become a valuable information resource.
I like to hang every day and rest only when required which seems to average out to 4 times a month. I consider the need for a rest day a set-back and optimize the weight/duration/frequency accordingly.
Start with less weight and focus on your set-up technique and the nature of the sensations that occur while hanging.
Keep a close eye on the tip of the glans where a red “Hickie” can form due to excessive vacuum that occurs with the application of traction.