Yeah I'm in the same boat with my flower light Currently.Any decent COB setup will be best imo. There are some very affordable setups out there (Timber, etc.). I went a slightly more costly route and got 6 individual COBs so I can raise/lower/add/remove lights at will. (cobshop.net) You can build any of them for even less money.
I switched from HPS to COB's and the difference in growth rate (everything else staying the same) is astonishing. Everyone who switches from the "blurples" to COBs are happy too.