Lure selection is always a gray area. I hate to list what I have had the best results with. To many differeant factors to list. Like said above most of the lure makes that have been around for yeas sell quality products. In addition several of the newer products are certainly quality material. I have just not had exposure to them. I use lure from many differant makers. A couple would be Russ Carman, Carol Black, Gary Jepson, Marty Smith and the list would go on for quite a while.
How may sets? That would depend on several factors. Weather, temperature, humidity and terrain. I smeer the lure on the backing or top lip of a dirt hole. When it is on the backing itself I cover it with natural material (leaf, tree bark. cow pie) from the area. This will extend the time it is putting out the aroma. On the average during fur season I use perhaps a teaspoon full at a set. I relure every five to seven days.
The most expensive way to use lure is not applying enough and it has to little or no attraction to the furbearer.
Roy