Predator squeal

[greybeard]

I know that many predator calls on the market make the same sounds, so it isn't unusual to buy one that sounds like another that you have. So when I found a call that I wanted and noticed are 5 calls on the market that seem very similar I wasn't surprised. However, I am interested in adding one, or all to my call collection and was wondering if anyone uses one of the below listed calls, and if they are DURABLE. I can imitate the sounds of the 2 that I've heard with other calls, but I just NEED more calls.( I only have about 25, or so predator mouth calls)

The calls in question are :

UK Fox Call. (you can hear it on youtube)

Haydel's sv-87 squeal type varmint call ( you can hear it on Haydel's site)

Wolfer's Harp (made by Crit'r Calls)

Burnham Brother's s-2 Close range and s-4 mini squeal.

Two days ago I made one that sounded like the UK Fox Call and the Haydel's, but the latex om my call didn't last, nor did another material that I tried. So since I have to have one of these I was wondering if anyone knows if the above calls hold up to a lot of calling.( I know that they will work, because I have called fox imitating their sounds)