A thousand times this. One of my projects is SMS heavy, and I had to switch it to Tropo because Twilio wouldn't do Canadian numbers. The developer experience has been far inferior.
The developer experience isn't even the worst of it. Try running some reliability testing. It's mind blowing how bad Tropo is and how many random hidden variables exist in their system.
Which is really sad when you consider the problem. API accepts SMS and inserts into database; workers take queue from database and action against SMS gateways (works in reverse for messages going the other way).
How can this be that difficult to do?
send me mail at patrick(at)twilio(dot)com happy to get you access to the ongoing canadian SMS beta