prakasa v viper battle

what ya all think is the best out of these two ? have only read up on viper so far and read good things , the prakasa i have yet to research . any thoughts ? any one used either of these brands ?
http://www.ebay.co.uk/itm/290671221796
http://www.ebay.com/itm/VIPAR-A300-LED-Grow-Light-300W-/181070802273?pt=UK_HomeGarden_Garden_PlantsSeedsBulbs_JN&hash=item2a28a92d61

the Prakasa can be found cheaper here (if your UK or EU located) and is even from a shop

http://www.growlights.co.uk/300w-led-grow-light-c-145.html?osCsid=je617sapjvq62basl4dbtu0ig1

also have a option of 500W but that cost a bit more

Nice link there . Thank you