I think you should stretch to the point you can comfortably wear a device 8-10 hours a day. As long as the springs are compressed 30-50% I think you are good. I don't think they should be compressed comptetely. That is too much. The science behind it comes I feel has already been explained. Further backing this up is those who compress the springs fully are the ones more often complaining about sensitivity and pain in the glans area after a short amount of extending time.
As to extending above or below the erect length I think the above paragraph will define for the individual whether you are above or below that mark.
Yes, good advice Funflyer. Philosophically I agree - who wouldn't? Just not doing that in practice!
I stretch about 1cm above erect length. I cannot stay in the noose fitting for longer than about 40 minutes because the head goes cold and blue and the Andro base cuts into the base of my penis (maybe I need an X4 girth base because my base is quite thick, unlike midshaft). However, I can easily stay in the Vacextender for an hour or so. Even then I check because I'm paranoid, not because the head is painful. The issue then becomes fluid build-up.
The issue for me isn't really shaft stretch pain - although it does get 'tired' at times. The real problems are base pinch and strangled head.
The official Andropenis "special" program is supposedly designed to get gains with a four-hour time input each day. On an average 15cm penis, the addition of rods means that the extender is out to
23cms within three months. This manufacturer approved, and supposedly medically tested program would mean that the extender would be massively over erect length at the three month point. So, they're doing it.
Personally, I never made it there and still haven't after eight months. (But I've gained about 2cms in length, I think.)
So ... I don't know. Seems like back to square one on this matter of opinion. That is, who knows?
More thoughts FF? Or anyone?