While I doubt adding mineral licks has any real affect on most deer, like me taking a vitamin, what can it hurt. I've played with any of the brands including those intended for cattle. Deer hit them all, I think mainly for salt content. Trophy rock works equal to any of them and if caught on sale at end of season not that bad of price. I find does, especially lactating and young deer are most frequent users of salt licks. I've observed them hitting them on cattle farms for a lot of years. I do find, they prefer when whatever form is used, that it mixes in with dirt, or stump material. They do like the stuff, and if you can find a natural spring/mineral seep, they hit it as much as anything. All of it tends to be overpriced but like anything, buy in offseason. Best use of it I've seen is late May thru hunting season.
As for the test, Tenure, LC did a very competant side by side test controlling as much variable as he could. I'm sure it is on his web page. Just a matter of fact test with no judgemental attitude thrown in. Might ck it out.