250 kPa = 2.5 bar. So it’s easy to read between the two, but it takes more mental math to get psi. For the MG4 though I would say the most important thing to remember is that the TPMS threshold appears to be around 2.4 bar, so if you run 2.5 you may start getting warnings on cold mornings.
A lot of people run more than 2.5 to stop this issue from happening. I normally top up to 2.8 bar (roughly 40 psi) and the pressures increase to 3.0 while driving as the tyres heat up. The highest they’ve gotten while driving is 3.1, which equates to about a 5 psi difference. That is pretty much the limit for pressure difference between cold and warm tyres, more than 5 psi is a strong indication you are under inflated and the tyre is flexing too much (hence more heat hence more pressure difference)
It’s possible your pressures don’t increase by more than 5 psi as well, but I prefer running a harder tyre regardless, so I don’t know if 2.5 bar heats up too much or not.