I veg under 42w and 26w CFLs both 6500k and 2700k spectrums to get ample amounts of blues and reds. CFLs are cheap and can be used through the whole grow. I'm finishing off a plant now with only 4 26w 2700k bulbs in a 2x2x4 space (l-w-h). That MH bulb will cost you more money in cooling that is for sure, that thing will run hot unless you have an aircooled hood, which is another additional cost. Grab lighting in your price range, make sure there's enough lumens for you're area, and grow.
KC : leaf: