So I picked up a nubby penis extension sleeve for my hubby and I to try, just to spice things up a bit and first of all it was extremely difficult to get on but then he said it kept feeling like it was going to slip off inside me. He also said it prevented him from feeling anything. Do you think it was because we were novice that it wasn't working or maybe just not a good sleeve? I would love some input from any of you who have tried them. Are they better with or without the tip on them?