i own both, and i like each one very much. the great river gets tons of use here for drum overheads, guitars, and vox. the singers with whom i have used it say it's the best their vocals have ever sounded. they do sound good. the great river does a good job capturing detail while giving some meat to the sound, as you might expect.
i have to give some props to the 2-610 applied as an ovehead drum mic on the last two sessions done here. coupled with a royer sf-12 and some killer NOS tubes, the sound has a lot of depth and an exceedingly pleasant high end. mine is an older unit, and it's great with a variety of condensor mics, too, when you want that present but smooth top end...
i had been using the mp2nv almost exclusively for my OH, but the 2-610 has replaced it here as of late. of course, the sound ultimately has to do with the player and his instrument. shitty cymbals, poor arrangement and technique will usually turn out less than stellar. my experience using a ribbon as overhead mic mitigates this somewhat since the ribbons generally seem to repsond a little better to equalization.
at any rate...love both of these pre's and would hate to be without either. the mp2nv is a stone work horse, though
