Well, my first grow I used Roots soil and the Roots bottled nute feeding schedule. I also ph'd the feedings to 6.5 everytime using General Hydro's pH products. If you have been reading enough than you know just from those two sentences I was doing a lot wrong. Basically, the harsh acids used to make pH up and down will KILL your "Microherd". These microherd are the key to breaking down organic matter(guano, etc) and converting them into a form that the plant can absorb. If I had known better I should have just used the roots products as the plants asked for them as opposed to some arbitrary schedule on a website and done so without using the ph up and down(i was using a lot too because Roots nutes will drop the pH wayy down of a feeding).
I am positive you can use the Roots bottled nutes very successfully with this understanding as well as an education on what each of those products actually does for them plant. I was the noob there and so I made noob mistakes. Every plant I had would get about 3-4 weeks into flower and then just turn to absolute shit. It's fine for leaves to yellow towards the end of flowering, but this was obviously something I was doing wrong and I knew that while I was still producing pretty decent flowers, I wasn't letting the plant reach its full potential and also severely hurting my possible yield.
I read some books(Teaming With Microbes) and got a much better understanding of what was going on below the surface of the soil. I knew I had to try something different so I took the Super Soil method. When I first started growing, I felt like the more products/snake oil I gave my plant-- the better off it would be. I wanted to spoil the plants but was really just giving them a bunch of shit they didin't need and weren't even asking for. Super soil makes everything"available" and your plant will take what it needs, as it needs it. The super soil "philosophy" is that the less you have to do to the plant, the better.
My first super soil run has just hit week 4 of flowering and the plants are absolutely flourishing. All the leaves are still green and the plants themselves are stronger. I am running a couple of the same strains as my first grow, so the difference is easily measurable for me. I'm not saying super soil is the only way to go, but if you aren't doing hydroponics than you are really missing out on the true benefits of a soil grow by messing around with bottled ferts and ph levels, IMHO.