Hello,
when we started to deploy 3cx for our clients, we used NUC5CPPYH, this model is tested and supported by 3cx (https://www.3cx.com/docs/intel-nuc-appliance/). It was fine.
Few months ago, our supplier propose us to sell another NUC version, NUCC7PJYH, at the same price (and say us he cant...