As a novice, and somewhat overweight runner, chafeing was quite problematic, particularly on longer runs. Even the judicial applcation of plasters caused some stress on my skin (let alone chest hair removal). I decided to have a go with this and was very impressed.
I use it on any activities where I will be sweating for a long time and therefore leaving sodium deposits which would rub. I am delighted to say I have been chafe free since I bought this product. Not only this, but it is as easy to apply as a stick deodorant. Exceptional and highly recommended.