I run a T5 quad unit. With my solarmeter I am achieving a 3-4 UVI index at basking 7 inches below the screen. I am running a 12% Arcadia bulb, 1 plant pro bulb and 2 6500 daylight bulbs in mine.
And to put that into perspective(and yes it looks like you get the same readings as me):
A panther needs 30-35 µW/cm² peak when the bulb is fresh, and should be changed at 15-20 µW/cm². Mind you, you can go higher as others have stated daylight is 300 µW/cm²
Now on to the scarry numbers:
Ohio august 23 2013 partly cloudy with sun peaking out behind cloud 11am: 3.0 UVI
Full sun 2pm 5.8 UVI
Full sun 2pm in the shade 1.5 UVI (measured under a few oak trees and bird garden shrubs)
42" LYR hood+ reflector no screen with 6% and 6500k 6 months old: 1.8 UVI @ 12" .7 UVI @ 24"
42" LYR hood+ refector no screen with 12% and 6500k 1 month old: 3.5 UVI at 12" 2.8 UVI @ 15" (beardy rock level)
With a 40 to 1 conversion for UVB µW/cm² to UVI, that would make the cham cage 72 UVB µW/cm²at basking and 28 UVB µW/cm²mid tank.
For the beardy that would be 112 UVB µW/cm² at basking rock.
ZooMed Reptisun 10.0 T8 tube, at 12 inches distance no screen (assume no reflector):
6.2 reading: 24 µW/cm².
6.5 reading: UV Index 0.7"