I've been doing it for about a year. It's worked a treat. A friend mentioned an APP that I could use on my phone which makes it so much easier.
I'm exactly 29 days a cycle and I know from my discharge (TMI soz) that I'm ovulating. We are VERY careful for about 5-6 days before I ovulate and then for about 2 days after and it seems to be so easy.
My question is...Am I really dicing with danger doing this?
The ob/gyn doc I was working with the other day said I was. 
We have 2 DD's and really don't want any more. Does anyone else rely on a similar method?