Speaking from experience having grown with "all of the above"....LED's only in the grow area will produce the healthiest plants to prepare them for the flowering phase!

In flower it is best to use a combination of LED/HPS to produce the best tasting and more potent buds...you can grow decent bud with LED alone and HPS alone but the combination makes for a better end result :jointsmile:

As far as the cost of the LED's....buy good ones and buy them from a company that backs the product they make! :thumbsup: