You also probably want to go with XR15 over XR30. Modular lighting is best and will allow you to spread them out farther. For XR30 you will want at least 4-5 XR30 turned sideways but I would do 8-10 XR15 for the same price. The goal is to make a larger multi panel style light if just used LED.
If going to hybrid, then I would still do the same with XR15 so you can more evenly space out the LEDs. I know they say you can do a 36" section with and XR30 but if your goal is SPS and you do not want to brown the base, then I would go at least 1 every 1.5-2 ft