People suggest the qb120 option for a reason. It is probably one of the most simple fixtures to put together and you can get all of the parts on amazon pretty easily. (Go to findchips.com to find the driver you want for like a 20-25% savings on it. Home depot or Lowes for some angled aluminum and screws. Get a really solid 260w 4 qb120 board for a total cost of around $225 with better spread and coverage than a qb 260 xl kit.
Other than that also check out rapid led growmau5 pucks (3000k with far red). For a first time buyer you can get 10% off and free shipping. Get a kit to save yourself money or have them put it together