After a few years with ADS:
Results: About 0.5inch over 2 years to BPEL. (this is after about 0.5 inches of gains in previous years)
Opinion: Safer to use than most options, but much slower. (I have put more hours into ADS in 2 years than all other stretching before combined, comfort = more time in device)
Suggestions: if you go with ADS I don’t recommend constant measurement, but do keep track. (one time every few months) Stay dedicated to the use of the device, when you miss a day get back on it as soon as possible. If you can only get 4-5 hours in for the day still do it (don’t skip a day because you cant get a lot of hours in). Take a break every 7th day from all PE, I find breaks help overall.
Problems: If it is a suction device make sure to remove all moisture and carefully dry after bathroom breaks or it will lead to problems. Change the stretch direction on regular basis (one or two hours) to avoid pain at the base of your pubic area.
Never Sleep with a stretching device or you may find yourself awake in serious pain with damage (If you wear a device enough you will find times you pull it off quickly because of pain, now imagine being asleep till the pain wakes you up).