One things start getting intense in video games, most people start sweating in the hands and that might make one's thumb slip off the control sticks and cost you the round. That's where Grip-it comes in.
Now I don't get sweaty hands a much (only on occasions) but the thumb sticks on my PS3 controllers have been put through the works. If you caught my "I finally got a PS3" post then you'd know that my first game was Ultimate Marvel vs Capcom 3. What am getting at is the left sticks on both of my controllers have lost the roughness they initially had. with all the hyper combos that me and cousin have been dishing out, the sticks got worn down fairly quickly. Instead of having to buy a new controller or replace the analog stick, getting a pair of Grip-it looked like the easiest solution.
The Grip-it covers are what they are, rubber covers for your analog sticks and they do exactly what the brand says. The rubber material used is pretty soft while doing a pretty good job of increasing the grip between your thumb and the control stick. It's also pretty neat that they can fit on either the PlayStation 3 dual-shock controllers or the Xbox 360 controllers.
I got mine at Game One Gadget for I think around 400php but it does give you two pairs so I'd say it evens out price wise. Here are some pictures of the blue and black Grip-its on both my Ps3 controllers. Long story short, the Grip-it covers are great. As for them giving you "the competitive edge", that's another story.