So I came across this for 28€ (about £24,25) while I was searching for a replacement for another Chinese LED that lasted about a year. It's running at 38W (includes power for fan).
Packaging and accessories
The instructions said to use it 50cm to 1.5m distance from the plant, but I've got mine running about 20cm from the new growth. This is the point the heat drops off.
Recommended continuous working time 10-16 hours.
Recommended for indoor use only (probably has issues with humidity).
Upon inspection, I noticed the diodes were pretty mucky! I decided to take it apart and try and clean them up. With a cotton swab and some rubbing alcohol, I managed to get most of it off. There was some residue that was too stubborn, but I didn't want to start using anything too abrasive, so I left it on.
Driver details
Heat sink (or lack of one
)
How it looks turned on (Note, it will screw with your eyes! Best not have it in a living space)
Note, this is the first day using it. Those plants were not grown with this light. I'll probably be taking them outside in a week or two, so I won't test this properly until the winter (perhaps that's why a lot of lights seem to be discounted at the moment).
I hope this post was interesting to someone.
Definitely requires a heat sink. Costs about 6€ with the power supply. You can also buy the two separate. This one wasn't very well packaged though. 
