Steely Dan is an interesting case. I've been pretty well mad for them forever - as my brother introduced me to them when I was youngish. However, I had a friend who always dismissed them as elevator music crap. Now there's a certain note of truth to that. They're extremely polished. Interestingly, some years later that same friend came back to me and faulted me for not doing more to turn him on to SD.
It's basically sort of light jazzy I-don't-know-what-you'd-call-it. The musicians are very, very accomplished. Don and Walter always knew exactly what they wanted and kept working on the songs until they got it down. I'd go so far as to easily recommend "Nightfly" and "Kamakiriad" - Fagen's solo joints. And I'm going to say that I would normally put the song "Royal Scam" into any listing I made of the greatest 10 songs of all time. Also, there's a lot of ironic/smartass humor in their songs. If they are more or less giving away mp3s, you really ought to have Pretzel Logic and The Royal Scam. "With a Gun", "Charlie Freak", and "Don't Take Me Alive" are all really nice caper/scam songs that I think almost anyone could really enjoy.
If what you are thinking of when you think of SD is the songs "Rikki . . . " or "Reelin' . . ." (both songs I enjoy) you owe yourself a listen to "Kings", "Black Friday", "Parker's Band", "Buzz", or "Show Biz Kids". * Having said that, I'd say that probably most people have heard the song "Kid Charlemagne" - I guess I'd say if that song doesn't convince you that they're a worthy band, maybe they aren't for you.
*(My perspective on this is the same as the way I feel about people who write off Stevie Wonder because he wrote "I Just Called . . .")
I switched some things around to keep things together and I don't know what . . . anyway:
I will add about clean/pure/overproduced that Steely Dan is very like Pink Floyd to my mind in this way. You could call it overproduced, or you could say these bands ended up with enough money and studio time and concern for their listeners that they decided to make things exactly right and exactly how they wanted them. It probably ends up driving producers/mixers/musicians nuts, but there's something to making things exactly how you want them. I'll admit, I listen to plenty of slapdash shit, and I don't listen to Pink Floyd much anymore, but there's a lot of very carefully put together music out there which is a pleasure to listen to.
In order, for me:
1) Royal Scam
2) Pretzel Logic
3) Can't Buy a Thrill
4) Aja
5) Countdown to Ecstasy
6) Gaucho
7) Katy Lied
8) Two Against Nature
I have not listened to Everything Must Go.
Honorable Mention: I also have a number of collections and other crap, and on Steely Dan Gold there's a (nearly eight minute) live version of Bodhisattva (a fine song) that features a spoken word intro in which a clearly inebriated individual praises a "Mr. Steely Dan" while the band members laugh.
"If it good to ya, it gotta be good for ya!"