Very Impressive Interface!
This is my first experience with an audio interface, so I have nothing to compare it to, but I am very impressed by the MOTU Audio Express.
First, it's very solidly built, with a thick metal chassis. In fact, it's so solid that if I were to ever stop making music (HA! fat chance), I could use it as a jack stand for my SUV in a pinch without a second thought! The buttons are all tight, no wiggling or feeling like they might pop off and all inputs grab nicely. Overall great quality look and feel.
From a setup perspective, loading drivers and having my DAW see all its inputs and outputs was a breeze, although never having used an audio interface before, I did have to consult the manual in order to understand a few basic concepts, nothing major though. It's a plus that it can connect via either USB (2.0) or Firewire.
The sound is amazing and being able to record audio (vocals or instruments) with latency so close to zero it's not even worth mentioning was what blew me away! The line input sound is very clean and uncolored. The mic pre-amps also are extremely clean and I'm sure they are neither adding nor removing anything tonally. Just crisp and clear and noticeably better than recording into my 24-track hard disk recorder with the same mics.
Now, the controls are minimalist by design, meaning the few buttons have several functions depending on what mode you're in and if you've pushed any of the buttons (they are both rotary and pushable). Because of that, this baby can do more than it may seem just from looking at it. It's a bit confusing at first, but the learning curve is pretty steep (contrary to popular usage, a STEEP learning curve actually means something is EASY to learn).
As I said, I have never used an audio interface before, but if some negative fate were to befall this one, I don't think I would hesitate to buy the same thing again, unless at that time I needed more inputs or something. You can certainly get less expensive interfaces, but I doubt they'd match the quality and performance of this one, and I think you'd lay a LOT more to get quality and performance that would be noticeably better.