Since this is your first project, I tend to agree with your friend. While there is nothing inherently wrong with starting with third party controls, you will find that there is much more documentation and help available for the built in controls. In your early development efforts, you will likely hit many stumbling blocks, regardless of the choices that you make. Therefore, starting out with the most well-travelled course may make things easier for you starting out.
Once you have a little more experience debugging some of the issues that you will inevitably experience while learning a GUI framework, then it would make more sense to start bringing in glitzy third party controls.