No direct experience, but a random thought. On my MR1, with unbalanced inputs if the incoming signal is so hot you have to turn the gain down below -6db, you will start brickwalling. it will look OK on the meters, but sound like crap. With balanced inputs, doesn't hit that point until -12 at least. Not sure if that applies to MR2 or not.
On a first outing with new gear, I would set the recorder gain to 0, and maybe even set the preamp to zero if you think it might be that hot. Watch the meters during the first song, it's ok if it's low... let's say it's at -20. At the end of the first song, adjust the step gain 7.5 or 10db as required to get you where you want to me. Then tweak a dB or two with the recorder.
I was listening to some DPA/MMA6000 tapes on the archive recently. Nice sound.