Hydronic Radiant Heat in Slab - Temp Sensor Question

Hello all, thanks in advance. I am new to radiant heat but read a ton over the last year. We are almost ready to install the pex and I need to know if the temperature floor sensor needs to be matched with the
thermostat or can they be mix and match?

That said, any suggestions for a good thermostat that is reasonably priced? Our thought is that unlike forced air, the radiant heat is going to stay pretty much constant?

Thanks,
Dean