I had been reading about all this Schiit and how the HD650 scales for quite a while and last month I finally took my HD650M down to a dealer here that has demo models. Here's my report. There were subtle differences between the units I tried, but the biggest difference I noticed was between the DAC on my iDSD and the Bifrost. This was rather surprising to me as I'd always thought the DAC would make the least difference. The next biggest difference was between the Mjoinir 2 and the Jot. Both very punchy but with different tonal balances and character. They didn't have a Modi Multibit to try, but from what I've read here (and experienced with the Bifrost regarding Schiit DACs), it's my next purchase for sure as it seems to be the no-brainer best bang/buck DAC in their line. Then, for only the HD650, I'd go with the Jot. But I need to go back and try it with my Andromedas before making my decision (plus save up some $ ). Hopefully by then Schiit'll have come out with a SE Pivot Point amp trimmed down of all the stuff on the Jot that I don't need.