Why these EZ crimps do not work very well is because there is a slight excess length of cable inside the crimp. Below image shows a standard RJ45 crimp with excess cable length marked "E"


With the EZ crimps, the excess is a lot longer, as shown in image below. It can be upto 1mm or more


This excess (also called stub length) is detrimental to high speed differential signals as they cause signal reflections on the cable. Below link shows a calculation on max allowable stub length on any transmission wire


In that link it says (Len = max length of stub, BR = baud rate) 

With 10Gbps link (which is speed of HDBaseT) the max stub length comes out at 0.75mm, which is smaller than what you get with the EZ crimps. Therefore please use standard RJ45 crimps rated at CAT5e and above