No problem!! HQI bulbs are pretty expensive. I'll be replacing my halides next month so I feel your pain. 20k bulbs have a lower par rating than 10k bulbs, so I would say the 10k bulbs are better. 20k have a blue look to them and don't require supplemental lighting. 10k have a white look to them, so most people supplement them with actinic lighting to get a blue/white look.