FWIW, we have both Telus managed service (in our case, ADSL) and Shaw in our head office.
I can tell you that in the 5 years we've had the Telus service there was only two problems, one they phoned me about, and the other was some dipshit with a backhoe. I phoned in to report the latter but they knew about it and were investigating already.
We have frequent problems with Shaw with latency. Prior to having both Telus and Shaw we had multiple Telus services and had zero issues with latency.
I would recommend the Telus managed service to anyone. Even if they do have to do maintenance on our circuit, I get an email a couple weeks in advance stating when it will happen and how long the circuit is expected to be affected so I can plan around it.
Also, the tech support for Telus managed service is light-years ahead of Shaw. I had an issue with the Shaw circuit and phoned the Shaw business support line and had to wait 70 minutes to talk to someone. Contrasted with Telus, where I phoned the front line support who created a ticket (no hold time) and had a call from the next level of support in less than 15 minutes.
This is the Business service from Shaw ($300/month) so it's VERY disappointing. I was expecting support levels like what I experienced from Telus in the past. The only reason we moved one to Shaw was for the speed but I'm not sure it's worth it considering the latency issues we've experienced.