Yeah I've done the code-in-a-google-doc thing as well. Wasn't a fan. I've also done the interview-right-after-work thing. Not a fan. I'm happy where I work too, but it doesn't hurt to always know what the market is like (as you're obviously aware). That being said I've found the "job market research" process tedious and tiring. Months-long processes only to end in frustration, lies about project scope/culture/etc., time-intensive programming exercises, and so on.

Not sure how else you'd handle it though, really. Busy people are busy.