ye try go with the MH for veging, as it puts out more of a blue light which is good for foliage growth, then u can switch to an HPS when flowering if u wanna pay a little extra...otherwise just get an HPS which should be right from start to finish..but the Sun is always better if u have nice weather and long days atm where u are....and if u are going to use artificial light try keep it on the plants all the time (24/7) for the first month then flower em if they a decent size...good luck