You can occasionally have a 'bad' monorail day with delays, etc, and once in awhile around here you'll read a really bad report, but (knock on wood) I've had great monorail luck in my travels - always dependable and very convenient. I've sat through a couple of computer re-boots which take 3-4 minutes, but nothing crazy.
The hours have generally been trending in a good way lately too, which hasn't necessarily been the case over the last few years. Here's a link to the current Times Guide:
http://www.orlandoparksnews.com/p/weekly-walt-disney-world-times-guides.html
As you can see, only Monday of this particular week has an inconvenient start time for both the resort and Epcot lines relative to park hours (8:30 and 9AM, respectively).
Hours change week to week, so make sure to check the Times Guide when you get there.
Have fun!