Bests & Worsts Reviews from Amazon

*** This rating has been edited from 3 to 1 because of obvious build flaws. Read my edit below to see how this can be overcome. *** First thing to address is the frozen screen issue many reviews mention. After using it for 40 days or so my meter also started showing a frozen screen. There is another review here that said re-seating the connector plug inside the unit was a fix. See the other review for a picture. Removing the back panel is very easy with the plug front and center. I adjusted the plug and the unit seemed to work fine after that. Then it started showing the frozen screen again (almost immediately) and after some playing with it I've discovered that when the cord has tension on it - stretching it to get the sensor in more distant spot, the screen freezes. There must be a loose connection in the cord itself. I have not disassembled the sensor to look there but since the cord has a rubber stopper molded into it to secure it in the both the sensor and body cases, I'm not confident the fix is in the body of the meter. So now I don't stretch the cord (or rotate the sensor which also freezes the screen) and it is working fine for now. Should the problem get worse, I might consider wiring in new wires myself. Not an option if your not solder friendly however. But I am willing to do that considering the price. The meter itself does a decent job and seems fairly accurate though I don't have a standard to compare it with. So take that with a grain of salt. Even if it isn't accurate, it seems consistent in it's readings so I can be confident I have a reliable way to gauge the amount of light falling on my plants. A quantum meter is very helpful for indoor growing so I recommend it if you can't afford a higher end model. It does feel flimsy as the plastic feels thin and a little cheap. It is not water proof in any way so keep it dry, though the buttons do have a complete covering so a little water on a finger won't be a problem. The read out is large and clear even though it isn't back lit. Of course, you're using it under lights so back lighting isn't needed. Why do I give it 3 stars? This meter is less than half of the next higher quality meter and 1/3 the price of an Apogee (the industry leader). I don't have $400 to spend on a light meter so this one fits my budget. As it is likely only some meters have the screen freezing issue, you have a good option here to take a chance. If you order one, I suggest giving it a bit of a work out on the cord (don't go crazy) and see if your's has a similar issue. Then you will have time to return it for a replacement. For me, I feel fairly confident I can make a repair if the screen freezes permanently. I don't mind tinkering and doing a little work on it to repair it is worth $200+ in savings. If the screen does freeze permanently I will return here to edit my review. If it didn't have these build issues it would be an automatic 5 stars. I don't think you can beat it for the price. *** Edit 2/25/18 Yesterday the screen froze permanently and I knew it was in the sensor housing. Opening it up -- a simple task with a single screw on the backside -- I could see that one of the wires had broken from the solder joint. I soldered it back together and it's good as new. However... The wires twist back and forth when the sensor is moved due to the wires free floating in the coiled 'wire housing' between the sensor and the meter. This is why I was having the screen freeze when I rotated the sensor. Even without the wire breaking, they were rotating such that two would touch and cause a short. This means the wires are likely to break again as one did while I was soldering the original break. To fix this, I put some hot glue on them at the junction of the wires and the coiled wire housing to lock them in place. If you do this, I stand by my above statements on it's value compared to other meters. This problem is a definite and serious manufacturing design problem and I would expect others to have the same happen with their units at some point in the future. My recommendation is to open the sensor housing and hot glue the wires in place before they break. It's quick to do and good insurance. I'm lowering the rating from 3 stars to 1 star since I think 95% of buyers won't want to or know how to fix the wiring problem in the sensor or possibly re-seating of the connector in the meter.. If 'I' read this review, I would purchase it since fixing things is something I enjoy and the fix is pretty low skill if you have ever soldered before, and isn't needed if you hot glue them in place before they break. But it is something the manufacturer needs to address, especially for a pricey purchase. If you read this review, than I think you should consider it a solid 3-4 stars if you hot glue the wires in the sensor immediately after purchase. If you don't like fiddling with your purchases at all you should stay away.