MRAD & MOA are both angular measurements.
I could type the mathematical derivation of both, but that just gets jumbled & confusing. So here's brass tacks:
MRAD is a "base 10" system, meaning measurements are in increments of tenths of a whole number. 1.1, 1.2, 1.3, 1.4 etc... very easy to remember, numerically...
MOA uses a fractional system, and there are scopes that can have 1/8 MOA, 1/4MOA, and even 1/2 MOA adjustments.
If you want a correlation between the two, 0.1mrad is roughly equal to 1/3MOA. So a traditional 1/4MOA adjusting scope is only slightly more fine in adjustment than a 0.1mrad adjustment would be.
Since 1 MOA meaures 1.047" @ 100yds, that initially makes the measurement easier for some shooters to get a handle on.
But many others find the base 10 mrad system more intuitively simple when dealing with dialed corrections and interpolating a mil based reticle.
Like everything else, it all boils down to personal preference and how you shoot will determine what might work best for you. A BR shooter might prefer a 1/8MOA adjusting scope to dial his POI in very precisely, where a tactical shooter might run MRAD since it's plenty precise and much easier to employ for engaging somewhat larger targets at a wide range of distances.
Whichever one you decide to try, DON'T COUNT CLICKS and DON'T think about your trajectory in inches! Once you break you mind of that vicious cycle, you'll be way ahead of learning curve.
What type of shooting are you wanting this new scope for?