Yes, all the time..
I've read that mh's might cut the yield back a bit compared to flowering w an hps, but have heard the.mh's bring out more terpenes compared to hps lighting ..
Right now I'm using sun pulse brand mh bulbs .. they come in different kelvin ratings, much like CFL's do.. I used the 6000 k for veg and the 3000k for flowering.. I have been loving the results and don't have any reason to change things up..