I've had a Node 2i for about a year and a half and can attest to the wonderful job it does, with only a minimal amount of fuss. But the one downside, which I didn't realize at the time I bought it, is the fact that its ability to scan, find and play content on my server (iMac) is limited to what's stored locally on the server's internal drive. Over 99% of my library, which is mostly ripped CDs that are managed through iTunes (or whatever it's called these days), is on an external drive, attached to the iMac via USB, simply due to its size (about 2000 albums, mostly in ALAC, but some AIFF). It just won't fit on the internal drive, which is where I keep my very small collection of hi-res downloads (about 30 albums).
In practical terms, that's not a huge failure, as I can use Apple Remote on my mobile devices to get that USB-drive content and push it to the Node via AirPlay. As I understand it, AirPlay is limited to standard redbook resolution, but that's not a big problem, as that's all I have in the iTunes library. It's just that to listen, I have to use a second app (Apple Remote) rather than the BluOS app that accesses everything else the Node plays - the hi-res files stored on the server's internal drive, streaming services, radio, etc. A minor pain, and definitely a "first-world problem."
I should add that simply acknowledging the shortcoming doesn't mean they're working on a solution. I haven't checked in with them about the problem in over a year. Maybe they're fixing it, maybe they aren't. I doubt it would be high priority for them.