I know this is an old thread, but I wanted to contribute because it seems popular for folks to Google an agency's name with "absolute water cooler" in the search string, thus pulling up the past thread for information on said agent.
I've been querying for a few months now, and the process has been much less painful than I imagined. Most agencies are prompt, and the rejections (while never completely easy to take) are usually not so bad to read.
Liza Dawson, however, was a bit of a slap to the face. I don't know if I got lucky, but the first few agents I queried had responses times of under 1 month. One responded in 18 days. I don't expect a two week turnaround from every agency, but Dawson took 76 days to respond. I wouldn't mind so much, but the first sentence of the rejection form letter is: "We're sorry for this impersonal response but we wanted to get back to you quickly." Psshh.
Anyway. 76 days to respond for this agent. Keep that in mind during your querying planning.