I just picked mine up directly from Solartech $259 shipped. Still worth it in my opinion. I want to put this thing to as much good use as I can.
I just remembered I have a couple of "old" Zilla Desert 50 bulbs. One I discarded after 6 months, the other was a few months old when I swapped in a ReptiSun 10.0 (which has a little over 1 month of use). I figured it was a good time to put them to the test against my ReptiSun. The results are startling and make me think that my bulb is defective.
No Screen:
ReptiSun 10.0 --- 6''-1.1, 8''-0.8
Desert 50 #1 --- 6''-4.1, 8''-3.0
Desert 50 #2 --- 6''-6.7, 8''-4.9
Arcadia T5 --- 6''-11.2, 8''-9.4
Screen:
ReptiSun 10.0 --- 6''-0.5, 8''-0.3
Desert 50 #1 --- 6''-1.7, 8''-1.3
Desert 50 #2 --- 6''-2.4, 8''-1.9
Arcadia T5 --- 6''-4.1, 8''-3.6
I also found that the Arcadia T5 is inconsistent along the length of the bulb. I have a 34'' bulb and found that at 10'' the output is highest in the center of the bulb. I measured readings from 2.7, 5.4, 3.8. I didn't notice this variation with the 18'' T8 bulbs.
I want to pick up a brand new ReptiSun 10.0 (and maybe a new Desert 50) and try this again to compare outputs.