i bought one of these a while back and no, its garbage, at least the bulb is. buy a reptisun 10.0 and put it in it.
i'm not sure how much it actually puts out as i don't have a meter but judging simply one the vast differience of light output between the zilla bulb and a reptisun i bought i would say its not very good.
the older version of this fixture was also notorious for causing eye problems in reptiles, they supposedly changed it but why risk it
here is the site that has test info on the old version of the lamp
http://www.uvguide.co.uk/phototherapyphosphor-tests.htm
50w/cm2 was read by them at approx 5" distance when the lamp was new with the plastic shield and about the same range with the shield removed after 105 hours of use (break in period) so that proves that their previous version was not very good, compare that to the reptisun 10.0 24" they tested it has well over 80w/cm2 at the same distance with no reflector (the zilla has a reflector in it that increases its UVB output by close to double according to tests they have done on that site with reflectors.