From what I have read, the spider farmer light is good. Here is what I see. That Spider Farmer light is 100w vs 125 for the one I linked to. Now if you add 10% efficiency to the latter light, it now gives you roughly 37% more light output. So, the light I linked to will offer more bang for the $ in terms of light output.
Going into geek-land, leds suffer from something called power droop as they heat up past their efficiency sweet spot and that lowers their efficiency. The heat sink in the unit I linked to will keep the LEDs quite a bit cooler, so they may well gain another 2-4% in efficiency over the SF light.
Last point. LEDs do not like to heat up past a certain point and it can shorten their life. There is a reason that the Mars Aqua lights sold as Pro versions have a heat sink. I would expect that the SF light will not last as long as the one I linked to.
By the way, their claim of 100,000 hours of operation is just plain silly. The 50,000 hours most manufacturers claim is a stretch.
The one plus for the SF light is that it appears to offer a 3 year warranty vs. 1 for the other light.
Personally I think the heat sink plus the greater output makes the Grow Light Canada the better pick.
Hope this helps.