I still like these lights too. I run three of them in Lumen Bright Mini Pendants.
I recently bought a Radium and put it in the center pendant and its not as bright as the PR bulb but the radium makes my coral pop. I really like the blue 20K radium color though so im biased.
On the other hand the 400W plusrite 20K bulbs are noticeably brighter, and have given me good growth AND I can buy 3 of them for the price of a radium bulb.
Its a tough choice and just depends on how rich you might be feeling when its light changing time. I think the price alone justifies trying one, my fish food costs more...