Make sure to check the color temp of the warm white LEDs. Most of the ones I saw while looking for my LED floods were in the 3000k range. I wanted 6000k+ and had to search for the cool whites to get 6000k.
Today i finished my new tank lights using the led floods. Maybe this will help you a bit. I have 4 of the cool white (6000-7000k) 10W Ebay LED Floods equally spaced across the top of my 36G tank.
I don't have a PAR meter but I do have a lux meter that outputs the lux for each of the RGB colors and a total.
At 18" depth my readings were
Red: 845 lux
Green: 729 lux
Blue: 561 lux
Total: 2120 lux
Using some of the conversion factors I've seen on various forums it looks like I'm getting a PAR of around 30. (this is only a guestimate)