I made a video where I compared a bunch of Mics and tried to get TH3 to sound similar. My Royer r121 and MXL r77 get compared. You also hear them compared with an sm57, km184, and AKG c414 xls.
To me, the r77 recorded at high impedance sounds similar to the r121 at low impedance. It has slightly brighter high end. I love it, btw.
It came with a pair of white gloves. Ha ha.
The r77 Mic is physically bigger than the r121.
For me, on loud sound sources it has been awesome.
The ribbon on the mxl is thinner than the Royer. Don't walk around holding the Mic with it uncovered. I use the plastic wrap it came in as a Mic sock to cover it when I'm moving it around.
Also, they say be careful of smoke.
While I'm sure they are fragile, I use them and haven't broken them in my first year of use.
I tracked a sax using both the r77 and the km184 for a CD not long ago. Not mine. The engineer loved the recordings.