That's what it's all about man. Helping others is the best part of the forum.
Not sure how much you know about efficiency or all that jazzy tech shit but I can tell you this from proven data. Kind led is 22.5% efficient. 22.5% of its energy is in the spectral range of solar radiation between 400-700 nanometers. That means that less than 1/4 of the energy you put into that box is going towards what you want it to. Platinum uses the same LEDs as kind which is epistar and they are one of the least efficient ways of creating usable light for photosynthesis.
I know we sound like salesman here but understand we have been through it and the few of us here now have tried and tested this tech against numerous other companies. I ran kind and it blew out 22 diodes in the first 2 weeks. My hps was sending sparks across my room and my pants were leaning towards an incandescent light bulb when I had 2 Mars hydros above them. Cob technology works and works very well. The 1.5gpw your talking about is most likely from other growers using the same equipment and definitely not from an epistsr fixture. Like hybrid said there are a lot of companies out there trying to recreate the Amare light and only for one reason, it works. The price of materials and peace of mind of the 5 year warranty makes it worth every penny. Newer lights use Cree 3590 cd bin cobs, meanwell drivers, top of the line Cree xp-g3 and xp-e2 LEDs copper core heatsinks, aluminum frames and stainless hardware. Sure an erector set DIY build will grow but it's missing the enhancement of the supplemental LEDs and uv. They can be added but then start costing you more and more till your at the point of buying one anyways. Trust me on this, I have 4 DIY lights running as we speak.
My opinion on this all is if money right now is an issue go to eBay and buy tbe least expensive light you can. Do a few runs and save for what will actually produce the 1.5 or more gpw your hoping for. The Amare not only has everything a grow light needs it has what other companies don't have while still being nearly the same price. That the enhanced spectrum, best warranty, customer service and support. This current grow is my third run under the Amare. My first run I pulled 4.5lbs from 3 lights and last run I pulled 3 1/4 pounds. If you follow along you'll see I'll be in that range again and this is from 75 day autoflowers too. It works