600W HPS/MH Ballast Question... With PIC!!

My question is this.

I have a (4) 600w HPS/MH ballast connected to (4) Xtrasun reflecters.

Is it worth the money to buy (4) new Metal Halide lamp so I can be able to switch them out when it is in the Vegitative stage, and then back to the HPS for the Flowering Stage. Is it really worth the money?

What is the advantage? Does it increase yield? Increase potency? What is the benifit if any? Thanks for the help.

-Mike-

yes you will see a big difference if you veg using a MH bulb (the plant uses more blue spectrum light and in my opinion the plant becomes more filled out) and with the HPS for flower (red spectrum the plant uses more for this stage and in my opinion it greatly adds to your yield)

mhfor veg cycle you want the blue spectrum and hps for the full spectrum