Just a ?

My question is.......Is it okay to put coffee in your morning Slimfast shake??? Before you get started on a tangent of pros and cons of Slimfast let me just say that I started drinking them because I have this horrible HORRIBLE habit. I do not eat breakfast. Well lately I've been having trouble focusing and lack of energy. I decided to check into the protein shakes. Way to complicated at 5 in the morning and they weren't balanced. I came across the High Protein Slimfast and was very very happy. You just pour milk and powder and shake it up. I have been drinking them every morning for a week now and I feel better. NOW here is where my question comes in..........Is it okay to put a little coffee in your slimfast shake (mine is chocolate so it would taste like a mocha)? It adds no calories just yummy yummy flavor.......not to mention that lovely kick of caffeine!!!

*UPDATE*
I tried it. I put about as much coffee in my shake as I normally put milk in my coffee. I LOVED IT!!! Of course it didn't hurt that it was caramel truffle falvored coffee either :)