I own a PG180 and like it very much. I feel for the price, it's as quality as any other brand's lights. But I will say that about any Pro-Grow light, as they are all made to the same standard now. The PG180, 155w actual draw, is a great light if you intend to (A) Grow 3 plants or less and (B) Use training / SCROG techniques. This light will not grow 3 plants AWESOMELY. It will grow 2 plants AWESOMELY. If you do lots of training, you could grow 2-4 plants under the PG180 with .65-1g/w average yields depending on your experience with the light. The more you dial in ANY set up, you will increase yield. If anyone is planning to use this light alone, it would be best suited for personal grows of small caliber.
The smaller PG90 is a single plant light or supplemental light. It has the same color and LED quality as their larger models. Some people have found moderate to great success using it as a veg light for 2-4 plants. I have never personally used it.
If anyone is going to get growing more than 4 plants, I would highly suggest looking at having a minimum of 450w of LED. Whether you split it between two panels or one large, you need to achieve ACTUAL WATTAGE comparable to the HID equivalent wattage if you expect to yield similar results. When planning your grow, factor in the actual watts your lights are pumping out. Add each light source up - whatever lights are being used - that is your final wattage. From there we benchmark 1g/w and say hopefully we are doing everything right on our end and leave the rest up to the power of the lights. So if you have a great set up in terms of nutes, medium, ventiliation etc... and use a total of 200-300w between whatever light sources (HID, LED, CFL, T5...) expect to yield at best 200-300 grams.
Moral of the story is a 150w LED set up will yield AT BEST ~150g. And that is if everything goes PERFECT, 100% efficiency. I feel some people forget this when assessing LEDs. Anywho, I use LEDs in my set up for a few reasons:
Temperature - I don't have an A/C or a portable. It costs a decent penny even to run a portable where I am, on top of its initial cost. Don't have the need for intake/exhaust fans as heavily. Can get by with one or the other sometimes. I don't use an intake fan, just exhaust. Passive intake works just fine.
Headroom - LED panels are usually pretty thin, letting the plants have more room to grow or allowing your set up to be smaller if need be. If I had an HID set up, I would not be able to move around in my tent like I can now.
Power Cost - It's cheap. They truly don't impact the bill so harshly because of their efficiency. I also dont need to run nearly as much cooling. Dont need to run an a/c unit, heavy extraction fans, or humidifier/dehumidifier. All of those can sometimes pull as much or more juice than your lights.
No Bulbs - I will never have to change a bulb or replace one. HID Bulbs can burn out as fast as 2-3 cycles, its not uncommon for them to die during the first run!
Voodoo - Unproven, but commonly talked about in LED grow journals is that people report
frostier nugs when using LEDs. Some people attribute the idea to the fact that they don't directly radiate hot air/heat at the tops of your plants, allowing resin build up that would previously not form due to heat. Heat degrades THC, so I guess it couldn't hurt to reduce the heat hitting the tops of the plants while maintaining proper ambient temps.
It's all about what works for you. I was originally going to buy serious wattage HIDs simply to get into it serious style. I became space limited due to life stuff and had to adjust. Now, after having one LED grow under my built and the second underway - I feel the potential and technology is really there now. All I gotta do now is step up my grow game as I am new to growing medical cannabis, the rest will come because I've seen the power of LEDs first hand.
I've been made a "believer" through my experiences.