I agree with the last comment. However, there are 2 aspects one should consider before embarking on this path.
1) Time, Effort and Ease of investing through individual fund houses through online PINs. If you have less than 4 funds, I agree with this approach. However, if you plan to have many more funds, you may want to reconsider.
2) Use of a consolidated statement: I know CAMS gives you this, but having a single window is far more seamless. I have invested (& invest) through HDFC ISA, FundsIndia and sometimes brokers. I have found HDFC ISA to be far more seamless.
Please note that the commission part is a contentious one (refer other threads on the same). I would say go for that which is convenient for you.
Happy Investing !!