Brett S wrote a review of Metolius Rock Rings CNC 3D on October 26, 2011
I just started climbing seriously last year and am by no means an athlete. I decided it was time to start taking climbing a little more seriously (I wanted to be better than my friends). I mounted them on the ceiling joists in my room and have been using them for about two weeks and they are incredible! In two weeks I went from barely being able to hang on the four finger pocket to hitting a max of 12 pullups! Like with anything else this tool is only as strong as your dedication, but if you've got the drive, this will deliver the results you want!
Only bad thing as a little side note, the bottom hold is advertised as a 3 finger pocket but I have average size hands and can only fit two fingers in them.