What do you like best?
Doodle is our standard scheduling poll tool - it's easy to set up on the back end, offers quite a bit of flexibility (for example, you can add advanced options like a "yes if necessary" options or time-zones, or you can leave the poll extremely simple.
What do you dislike?
If I had to identify one problem - it's the display/user interface on particularly large polls. When you have lots of days with multiple times, it can be a little unpleasant to scroll through all the different options.
Recommendations to others considering the product
Look through the advanced options each time you set up a poll - there are a number of options in there that are quite helpful, but many of them can not be activated once you've set up the poll, and there's no easy way (that I've discovered) to quickly recreate an old poll.
What business problems are you solving with the product? What benefits have you realized?
Scheduling is a nightmare, no matter how many people you are dealing with. In my work, I often have to coordinate phone calls and in-person meetings with dozens of people. Doodle has proven to be the most effective tool to finding agreeable times for everyone, or at least as many people as possible.