Even I use MI.
But whatever spec Xiaomi offers they can't match OnePlus. I'm using Mi A2(Android One) every security patch update is a hit or miss. Solve 1 problem 2 new bug arise. After Apple,Google I think OnePlus is the only company who provide guaranteed 3-4 years Software update. And their Oxygen OS is faster than Google Pixel Stock Android.
OnePlus 7 is the most bang for buck device within 33000 currently. And OnePlus resale value is much higher than Xiaomi.