I've not used those monster bulbs, so I'm not sure how much heat they give off. It will be an issue, but probably not a huge issue. I imagine you could rig a small computer fan next to it and that would take care of the heat issue. Just don't blow the heat down on your plants.

You know the basics about the kind of lights required, and your calculations seem correct, you are just going to have to choose what you think would be best for your situation. If I knew I was going to do a much nicer set up next, I would try to save my money for that. Then again, as you said you could use the bulbs you buy now, in your next set up. It may be smart to buy a little more light at this point and figure the new ones into your next design.

I don't know if I'm helping, sorry, a little buzzed.