The $5 cfl bulbs would not be a good alternative. They have penetration issues that are really not worth trying to overcome. Reflector technology can do a lot for this; but would it really be worth the hassle to try and design & implement one for this when mh & t5 are readilly available & inexpensive?
Mh is king when it comes to pentration. This allows you to have deeper water or raise the light well above the tank, avoiding heat issues. Par per watt is greatest with mh, or was last time I checked. With new advances almost everyday, this could have changed, but I doubt it.
A cfl doesn't provid enough par to accomplish anything. With 6 bulbs at 26 watts each, you're consuming the same power as a 150w mh. Taking into consideration the increased usuable lifespan, par & fixture availability of the mh, it would appear pointless considering using the cfl bulbs.