Holy Synchronicity, Nigel and Jay!
I did a lot of research before selecting the Saffire. Its predecessor was an 828 Mk2, which left big shoes to fill because it was my mixer as well as my interface. I had to have comparable inputs and routing capabilities. Unfortunately, the overriding criterion was price because, as I have whined about so often, I haven't been this broke since college days. I scored this unit on ebay for $339, less than half the price of an 828.
The Saffire was a near-perfect replacement. I didn't even have to cut any zip-ties from my neatly bundled cables; everything plugged right in. Installation was a breeze, just a little weird when I had to answer the "found new hardware" dialog three times (Windows sees analog, MIDI and S/PDIF as three separate devices).
I hear a tiny bit more hiss in the speakers than I did with the MOTU, and it sometimes makes popping noises when I change settings. But it does do one thing better: it remembers what volume I left it at. The 828 had the annoying habit of defaulting to full volume every time it was turned on, which more than once made me fear for both my speakers and my ears! (The real problem is with the ADAMs, whose gain is too high even at the minimum setting. That also accounts somewhat for the hiss, I think.)
I've only had a couple hours with it so far, and haven't done any recording with it yet. But I can't tell you how overjoyed I am to hear music coming out of my computer again! It's been 2 long months!
One of the deciding factors in choosing this manufacturer was the general consensus that Focusrite customer support was good. I tested that even before the unit had arrived, emailing a question to them about the Mix Control software. They answered promptly, gave me the information I needed, and followed up a few days later with a satisfaction survey. With any luck, that'll be the last time I'll need their help, but it's good to know they're on top of it.
Time will tell. Over the years I've saved all my SONAR crash dumps and kept track of why the crashes occurred. Far too often, it was the MOTU driver that was the instigator.
I did manage to crash SONAR last night, but it was SONAR that croaked, not a driver nor a plugin. I had removed all references to the MOTU in AUD.INI, editing it from within SONAR and then reloading. Apparently, SONAR was unhappy about that. Everything was fine after restoring the original AUD.INI.
I still have one mystery to solve: every time I start SONAR I get a warning saying "No MOTU device found". Well, duh. It ain't there, so give up already. But that's a mystery for another day - for now, I'm enjoying the return of sound.