Ok, I am officially shocked. I just received both my Solarmeter 6.5 from Lightyourreptiles.com (an EXCELLENT experience, and the lowest price out of everywhere) and my new Powersun 100W SB from Amazon. Went ahead and tested everything I could think of - the sun outside at 3:32PM: 05.6 - 05.8 on the LCD display (I assume this is 5.6-5.8 according to previous posts about measuring UVI)... My 4-month old SolarGlo: 0.01 - 0.02 with the meter directly under the bulb at the bottom of the rock Leo basks on (the height of the meter makes that about an inch HIGHER than his back)... the "interim" compact Reptisun 10.0 I've had for a bit over a week: 01.2 - 01.4 if positioned horizontally at 12 inches or so (unfortunately it is actually installed vertically in the dome, and that gives a similar 0.02-0.04).. and the real kicker: the brand new Powersun: 0.00 - 0.01 at 12 inches, goes up to a whopping 0.04 if meter is held at about 6 inches... making it the weakest of all! The bulb is nothing like the Powersun of old, that I remember was hurting Leo's eyes. It is smaller and feels cheap and flimsy, and has that milky coating on the INSIDE of the glass.
Anyway, what the hell do I do? No wonder Leo improved only marginally since installing the Reptisun and burning it alongside the old SolarGlo... at least his temps were good, and he MAYBE got 0.5-0.6 out of it all combined. I replaced the battery just in case, no change. Do I maybe burn in the Powersun? I kinda doubt that would help. Are my readings incorrect somehow? And how the hell do I return a bulb bought online.. I'm sure there is a way, but what an inconvenience!
Also, I found a great local store literally yesterday (clean tanks, visibly happy animals, quite a variety, I was really impressed), and they had a large selection of bulbs I had never even heard of.. repti-something is all I can remember, but they were definitely MVB, and even had that in 60W, to my surprise. I may want to go back and check some of them with my Solarmeter...
Edit: I called Zoo-Med and spoke with Shane in R&D and he told me that I was essentially measuring a regular bulb, as the filament inside only starts giving out UVB after about 30 minutes of use, so I am taking that back. He also said the Powersuns have never chenged shape or supplier, so it really should be the same as the old one. Maybe I was just thinkign of something else. So I'll give it a bit more time and report. Overall a very pleasant customer service experience I must say.