Does anyone have any experience with XM 400 watt 20ks? I have to replace all of the bulbs in the 1,500 over the next two months and I am thinking about switching from radium to XM. I have always used radiums but It would be sweet to save some money-I understand the phos. burns up a lot faster in these bulbs but the tank only has lps and softies. Any input would be great on color and overall look.