Using Nunit Frame work or Creating Visual studio Test Projects which one is the best way to save the time and effective automation?

Now i am using selenium IDE to script the maximum parts in my application to reduce the time of execution(i feel ide execution is faster than test project execution) using gotoif, while, regexp ..etc and would go Selenium RC only for data driven methods and the events which have not been handled by IDE.

Please suggest me Am i in the right way? because i am in the beginning stage on Automating my applications asking this Question for early correction is better.