HPS can veg and flower.
CFLs can veg and flower.
CFL's are better at vegging. HPS are better at flowering. if u have the money get both. if not, then which ever u want. i went with CFLs because its less elec bill and less heat.
HPS produces better bud in flowering. so for the best alternative. CFL's to veg, then HPS to flower and u will get nice big buds etc etc