I don't have any personal experience with these led fixtures and I am BY NO MEANS SOLICITING FOR THIS MANUFACTURER!!! I have just done a lot of research on most of the top LED manufacturers and I have concluded that the Hydro Grow Penetrator 336X-Pro (the one you linked to in quote above) seems to be one of if not the best, VERY EXPEN$IVE, however I believe in this case that directly translates into quality. Every aspect and component of this light was specifically designed for indoor plant growth, the lenses alone are the accumulation of 4 years of research, seems to me these guys know what they are doing. They claim its the most powerful commercial grade LED grow light in existence, among many other claims like their exclusive X-Lens technology with "uniquely engineered amplification optics" which increases the output of light intensity by 5-6x that of most competitions generic lenses. Another very cool feature that answers the OP's question in the first quote above, its modular, meaning user-serviceable/upgradeable, if a few leds go out you don't have to replace the whole unit just the section that needs it, that's pretty dam cool. They are also linkable so you can attach multiple units together without the need for extension cords or adapters another user-friendly feature.
Please understand that I'm not trying to claim that this is the absolutely best LED grow light available, I'm merely passing along my opinion based on research Ive done and not personal experience, however like I mentioned I did a LOT OF RESEARCH! Hope this helps and good luck with whatever you decide.