I hear where you're coming from, R-15. To be honest I did have some issues with one of the card slots failing to respond initially. Now, before I start calling I confirm that all three slots are working. If they're not, I have a little 2 minute trouble shooting routine I put the caller through and it always get all three slots working. Once I've done that, I've never had it fail me on a stand. The battery compartment on the remote was a little tight at first, but there is a rubber pad that you can shave down to fix that problem.
You might be thinking why go through the trouble? Why not just by something that works? To which I say three things. First, the sounds are first rate, especially the fox sounds. Second, at 189 dollars it's at least three hundred dollars cheaper than a lot of other callers. I've seriously considered getting another brand of e-caller, but they all seen to have some issues. With the WTs, I don't like the need for 8 AA batteries and the remote doesn't look real user friendly. I'll put up with a little aggravation to save the bucks. Lastly, you might want to look into whether or not the above listed issues with the Preymaster 4 have been resolved. I bought mine when they first came out. Later generations may have had those problems fixed.
I don't have anything against Foxpro or WT. If you've got the bucks get whatever you think will work best for you and best of luck to you.