Before I get responses on to what the difference is between the two are, I do know what the differences are as far as one(TLC) is for foreskin restoration and has a small hole on the cone to release from the head to pull just skin, the other (VLC) does not have the hole on the cone and is supposed to create a suction on the head to pull the entire penis. My question and concern is how do you know the cone is actually creating a suction? If I put the cone on the head of my dick it does not look like it could create any suction at all. There is actually a gap around the very edge of the widest part of the cone and this has me concerned that it is releasing off my head when I put tension on it. The reason I am questioning this is because I am getting a lot of extra skin which I know is good to a point but I also want to make sure I am getting proper stretch thru out the whole penis and not just the skin. So how do I know? I feel a lot of skin stretch and my ligs feel tight but is that just because the skin is being pulled hard enough? I don't know. Any ideas?