Hey, thanks for the replies, guys. I'm well aware that it's a tired question and I've been researching the crap out of this but there are subtleties I still haven't figured out. My understanding is that the Great River is good enough for high end studios, while the Mini-Me isn't as good but can hold its own, especially as an all-around unit. It's just that I don't want the weakest link in the chain to collapse the whole project.
Talent I've got. Music I've got. I'm working with an old friend and we've pursued other careers (in retrospect I can say it was out of fear, mostly), but since hitting 40 we thought we'd better shit or get off the pot. So we're on a budget but we do want to get the best recording possible right now, and not just prepare for future projects.
What I'll ultimately do is purchase from someplace that will let me try them out first, and make a final judgment then. But if any more of you with better ears than mine wants to weigh in, it would be much appreciated.