I would encourage you to steer clear of the buples if possible. They certainly work, but there not nearly as efficient as a newly engineered light.
Try and obtain samsung diodes, if at all possible... But regardless, stick with full spectrum diodes, that add in deep reds, and hopefully some UV+IR
If your on a budget, consider something like this:
Bridgelux LEDs Spider Farmer SF1000D full spectrum LED grow light with dimming control and high efficiency, and ideal for beginner indoor growers.
www.spider-farmer.com
If your going to do a 2x4, I would simply get two of them.
or something like this:
https://www.spider-farmer.com/products/sf-2000-led-grow-light/
IMO, your actually better off going to say a 3x3 and doing something like this: The SE versions of lights are simply better units overall, and penetrate the canopy better, overall.
SE3000 300W Led grow light with Smart Bluetooth & Wi‑Fi app control with sunrise/sunset simulation, temperature-based dimming/shut off —ideal for 3×3 ft grow tents, for all growth stages.
www.spider-farmer.com
Personally, I trust the spiderfarmer brand, (and the fact that the support the forums here) but there are certainly many quality light manufactures out there as well.