The problem I see with some of these products in a jug, is they are attempting a one size fits all approach, And the price goes up due to extraction, refinement, and packaging. If someone came to your farm and told you that all you need is this particular NPKS fertility blend, would you buy it? Probably not, because you know from experience on your farm that it isn't going to fill all your fertility needs.
It all depends on what you have in your soil to begin with. Find a lab that will spend the time to identify what micros you already have, and in what ratios. Pull some tissue samples throughout the season and try to identify what plant deficiencies you might be experiencing. If your low on P maybe you need more 11-52, or maybe you just need a little zinc. A little molydenum goes a long ways in helping the plant metabolize N. Many of the trace elements need to be present as they are catalysts to fire an enzymatic process to metabolize a macro nutrient. A plant will withstand periods of reduced solar light if it's Magnesium needs are being met, as Magnesium is the center of the chlorophyll molecule. A little fulvic acid seems to help also if it's cloudy or smokey for extended periods of time. Many of the traces must be present for cell formation and function. Plants will withstand drought conditions better with a full spectrum of micros present, as plants don't necessarily take up water because they are thirsty, they take up water to trans locate nutrients and the more nutrient dense the water is, the less water they take up and transpire. To much N and plants will become water logged and less nutrient dense, thus making them more susceptible to disease and insects that must be sprayed for. There is a side effect to any application made to a crop/soil. Do you really think a fungicide is only killing the pathogens? There are numerous studies out there if you look that identify certain trace elements having direct control properties against certain pathogenic organisms. Dr. Don Huber did a lot of research in this area.
There are a lot of inexpensive products available that naturally contain trace elements. Soft rock phos is a good example. It contains more calcium than anything, than P, than 60 some odd different trace elements. There is a product out of Utah called Azomite that is basically just mined trace elements left behind from an ancient under water volcanic eruption. I know a farmer in western Wyoming that sees huge responses in his sandy soil from applying trace mineralized salt from RSC (redmond salt and clay) also out of Utah. There are also products on the market to help with P solubility and tie up prevention. I see a big response from this type of product due to the soils on our farm naturally being high in Ca and P.
As for third party, unbiased, trial studies, I don't hardly believe they exist anymore. Every university is on the dole from the chemical companies, and if you have enough money you can eventually come up with whatever data you require. In some circumstances the researcher may decline to even test a product because the big boys threaten to pull funding.The fertilizer lobbies have a tremendous control over what data and products we as farmers see. Small companies that might actually have a farmer's best interest at heart, can't afford to jump through all legislative hoops, so they exist in an almost covert underground environment that makes it very easy for the big players to make fun of and shame should they gain any traction in the market. There is no better testing environment for your farm, than your farm. Install yield monitors, do test plots, read, study, don't be afraid to trial something because it might not work, BE YOUR OWN AGRONOMIST, nobody has more interest in the success of your operation than you.