The MRC won't give you an in room frequency response graph
It does, look at the Measurements tab, right-click, View Plot. Choose Low Frequency Response.
I will concede that REW is much easier to read and can provide the relevant filters required but you can achieve decent results using MRC's built in calibration. I don't find MRC's auto filters that useful, personally, but you can tinker with them and adjust that Low Frequency Response graph in realtime.