Its rare that you're going to find anyone with hands-on experience with ALL THREE.
I can tell you that my 828mkII (a driver and hardware twin of the 8Pre, just less preamps) has been rock solid.
Sorry, but if you don't want to search out info and product reviews, we can't empty our bank accounts just to serve you....
I can get about as close as anybody, I think. I've used the 8Pre and the FIREPOD (the FP10, basically). Echo Audiofire is based on the same chipset (BeBoB). The BeBoB hardware (FIREPOD/FP10/Audiofire) tends to use more CPU power than the MOTU while still being prone to CPU spiking. I can't imagine why that is the case since normally spiking is caused by attempts to reduce the average CPU overhead, but that is what I've seen.
I'm very impressed with the 8Pre. I wouldn't even consider trying to record more than 8 channels at once with the Presonus gear, as I occasionally got glitches even with just a couple of channels (though it wasn't really any less stable with eight, so maybe it wouldn't have been any worse with more...). This is with a four core 2.5 GHz computer (two dual core CPUs), BTW. With my 8Pre pair, I do 10 without breaking a sweat, and I'm pretty confident I could do all 16 without glitches. It just seems much more robust to me. YMMV, of course.
Oh, and I've also used the M-Audio FW1814 and the M-Audio Delta 1010LT. I'd recommend the MOTU gear over both of those so much that I can't even begin to say how much....
The Delta 1010LT audio seemed pretty... fuzzy, I guess would be the word... lacking clarity... when compared with any of the other three interfaces.
The FW1814 sounds pretty good, though it has some interesting bugs when it comes to sharing the bus with... anything else. The S/PDIF hardware pretty much keels over.
