RME Fireface 800
The RME line has a solid reputation and for the price the FF800 is a great deal. After using it for 3 years on hundreds of sessions I'm pretty familiar with it.
The Good:
The totalmix software give you great VU - fast and accurate so you can keep away from distortion, the #1 enemy of digital recording. Its almost worth the price of the box by itself. You can use it to control monitor volume - anything, in the hardware, from a window.
The converters are good, you can make a great record with them. They are thinner sounding than and less punchy than the great converters (Lavry, Apogee, Cranesong etc.) - but really, not a weak link unless all the other parts of your studio are up to the very best standards.
The Bad;
The pre's are not so bad really, but so-so. The same pre in their 4 channel box goes for 100 a channel - so its a good deal - but you will not get the smooth fat juicy sounds you would expect from a really high end pre 10 times the price - nor do you get the controls. They are handy though for scratch tracks, and line in's.
The Firewire interface works fine most of the time - but I suspect its responsible for a few "errors" (bit errors) recording. There's a lot of very scary documentation about reasons why XP might not give full bandwidth to Firewire you will find in the technical documentation. I recently hooked up a Motu Traveler - which is half the price, and had not a single bit error recording through its FW interface. Its Apples to apples - recording 10 tracks at 32/44.1 under firewire - the Motu seemed to handle it with no problem, while the FF seemed to struggle. Nothing hard here - I'd still take the FF over the Motu in a heartbeat - its much easier to work with and sounds as good and has a lot more channels, options, etc.
Also, there are some people who swear PCI sounds better than FW. There is a good reason for this, having to do with the fact that FW goes through a comms interface and then to the PCI bus - while the PCI interfaces go directly to the PCI bus - but I have not personally experienced the difference.
The Ugly.
Last month the thing went into a failure mode that pulsed noise bursts out of every channel as its way of telling me it was dying. It almost destroyed a lot of very expensive gear downstream, but I guess I caught it in time. It did this with no provocation. Also, it took 10 days to fix. I'm scared of it now and I think I'm gonna have to find a new solution before the thing blows up my Focal Monitors. Maybe its a one in a million failure - but how can any engineer allow a situation where a digital box can blow up downstream analog gear? They have total software control of the box, and a back up battery - which means it could simply turn down the analog outs in its last breath of sanity.
Upon the failure - my dealer told me it wasn't his problem, I should call the distributor. The Distributor, Synthax USA, was very polite, and told me they had to ship it somewhere to be fixed and the truck comes on Wednesday. When you buy really expensive stuff, usually, they will take it back, and fix it right now, and try to set you up with a loaner. Mass production has its advantages - and its drawbacks.