Equipped with a 4200mhz RAM module supporting 3700 MHz memory timings.
No, a 3700x socket typically supports up to 3200MHz RAM, not 4200MHz.
It depends on the memory controller built into the chip. A solid IMC can handle more than 5000, but on my 3600 any model with over 4200 won't start.
Perhaps, but if you're aiming for value, you shouldn't