Hey buddy,
To give you a balanced opinion...
Many users on this forum chose to use T5s or fluorescents as the lighting for the vegetative state. When it comes to flowering, some will go for a Metal Halide Lamp, but in general, most will take the HPS because of it's intensity of "red light".
Simply speaking, an HPS is probably the most practical solution for both stages due to it's documented sucess.
However, fluorescents are also practical due to the fact that they don't emit so much heat and don't need that much electricity... You decide.
Happy farming,
-Rich