I have a very experienced neighbor who got me started using Mineral-lyx.  The main reason being that it works to minimize health problems in a cow/calf operation in our particular soils and forages.  I'm not a nutritionist but there are several components of Mineral-lyx which are important to preventing calving problems. 

The problem is that it is tough to conclusively prove in an individual herd without a carefully designed, long term and complex large scale experiment. I am not interested nor capable of doing that.

I find that my consumption and mineral cost per head per day is very minimal, especially after several tubs have been out for awhile and consumption stabilizes.  I did try cheaper bag dry mineral in circular feeders with rubber tops. There was very little of the bag mineral consumed. Most turned into rock-like lumps in our climate and was eventually wasted.

IMHO having Mineral-lyx barrels out is producing a positive, if hard to quantify, ROI. It is not "candy". Its ingredient list does get consumed and there is zero waste.  The fact the manufacturer uses the hardness to control consumption is fine with me. 

As long as the ingredient list is correct and I see cows, calves and bulls all actually consuming it at what I feel is a reasonable cost/head/day with no waste, that's what's important.  The payback being almost zero herd health issues and almost zero calving issues. There are obviously many factors involved in herd health and successful unassisted calving however I believe a good mineral program is one of the major factors.

(IMG007 Cow 51 with her 6 month old Tested sired calf 112 101518 (full).jpg)

IMG007 Cow 51 with her 6 month old Tested sired calf 112 101518 (full).jpg (161KB - 259 downloads)