We took the Megabus from Washington, DC to Toronto and the ride was just perfect. It's cheaper than the other and we suffered no delays (we even arrive too early). The Wifi wasn't working that well but it was ok (it just works in the USA). The power outlets were not all working but we had also USB ports which were sufficient to charge our smartphones.
The place for the legs could be too small for tall people but it was ok for us. So nothing to complain about.