I have 750W worth of Blackstars...They are great LED lights, I would highly recommend them. They have some of the best deals on the internet and their products are legit. The 240W is pretty nice, but I also have their 500W and that shit is out of control. The UV spectrums hurt the shit out of your eyes (not so much in a brightness way, but in a pain way), but they pump up trich production like there is no tomorrow. I have a hybrid grow room going, *both hid and led, as well as a plain LED grow going, and a plain MH grow going. The hybrid grow room kicks the piss out of straight HID or straight LED I have to admit, but I love just using a plain LED, so little worry involved with bulbs going out, moisture, heat, electicity, plants getting too close, yadda yadda yadda.
All forms of grow lights have their advantages as well as their disadvantages. HPS's foot print kicks ass, but there is a lot of waste involved, and little UV emitted. MH has a good footprint too, and good UV output, however there is SO MUCH waste when you look at what is needed for flowering spectrums. T5's are good, just takes a lot of adjusting with plant heights, and the proximity to the canopy stiffles its foot print. CFL's are good too, a bit hotter, and they have distance issues. LED's are laser focused on precise spectrums, have little to no waste, however, their foot print is their limiting factor.
Blackstar has prices that disarm most "you'll spend at least 1000 bucks" arguments. I didn't believe that they could sell a decent light for that money, so over vacation when I flew back east (I come from around suffern) I stopped by their shop, and saw in person. Purchased them on the spot. I have a bit of trouble with a subterrainian grow room in that the temps are too cool without artificial heat, so I used my HID as a source of both light in heat in conjunction with the LED.
I currently have 5 snow white going under just a plain old 240W and nothing else, they are doing fine.
My big plan is to have two 50/50 wattage LED/HID grow rooms. 480W Blackstar LED (2 240s) and 500W HID (2 250W HPS or MH) and see what that produces. This way you get the foot print of HID with the precision and UV of LED. I plan of growing the same amount of plants, just larger, in larger buckets to facilitate a higher yield of higher quality bud without spending extra on another HID + the electic that goes with it.
I don't know much about blackstar but I do know they are better than the crap on ebay. I think growledhydro would give you more bang for your buck, but you might have to wait an extra week or 2 to get yours from them.