If you've ever ruined a fretboard, because you didn't want to go through he hassle of taping everything off, this is for you. I bought this for a friend, because he taped off his fretboard with the wrong kind of masking tape. He used the old style tan colored masking tape, on a maple vintage Fender fretboard, to polish out a few dings he got on the frets. By the time I got over to his place, the tape had been sitting on the fretboard for at least 30 minutes. When he went to remove the tape, all of the old nitro came off with it. Not cool at all. Now I'm refinishing the whole darn neck for him and a new set of frets. Next time he needs to steel wool his frets and polish them up a bit, he can slap one of these down and get right to work without worrying about whether the new nitro will come off (it won't, but still....) or whether or not he will get fret dust ground into the maple.
For Pros: I guess the best I can say is that it saves you so much time. Taping off is a pain. Also the cost of these are so affordable, I bought myself another one for myself.
Cons: really? I can't think of any. Can you?
It's a great time and money saving tool that is essential for any kind of fret work.