I got my [words=https://shop.mattersofsize.com/products/sizegenetics-penis-extender]SG[/words] last week - but still, I do some research on its efficacy.
Digging the web I bumped into collection of scientific experiments related to urology field.
One of them discus the efficacy of “Daily penis stretching technique”.
The bottom line is that using an [words=https://shop.mattersofsize.com/products/sizegenetics-penis-extender]extender[/words] device for 4 months gave an average length gain of 1.8 cm (0.7 inch) and varied from 0.5 cm up to 3.0 cm (0.2-1.2 inch).
Check out this article and look for experiment P-155.
http://www.nature.com/ijir/journal/v14/n4s/pdf/3900961a.pdf
So I guess the answer is YES - it works...