Been using fox pro for years. The sounds are very realistic and they work! Just depends on how much you want to spend and how serious you want to get. Yotes are smart and its gonna take some time to figure them out.
I was coyote hunting one time and had the Alpha Dogg on a tree stump playing a wounded jackrabbit call. I called in a group of eight mule deer and the biggest, a big buck, walked right up to the caller and was staring at it for a few minutes before I finally waved my arms and scared them off.
I have the two Fox Pro units. Older original unit 32 calls. Newer unit 500 call capacity. Both work great coyote, fox, crow, racoon, rabbit, deer, bear etc. on my 500 capacity.
Def Fox Pro all day long. They have a variety of calls, there sounds are great always coming out with new stuff. I have a hammerjack which works well in close ranges, but if you are calling over great distance you may want to go with the new one with the double megaphone, "Xwave". I have hunted over that one and it is LOUD, which enables you to call to them from greater distance. FoxPro has great customer service and from what I understand they are 100% made in USA. Check out there Youtube video's, specifically Al Morris. Very entertaining. He also does seminars at the Harrisburg Sportsman show going on this week.