I have had Shaw 50mb service for a few months. I have had tons of problems with varying speeds, dropped wifi connections etc.
I had a service visit where the tech, who was superb, installed a signal booster as my line is substandard. We then had an average of 44-48mb. However this dropped off very quickly when you moved to other rooms and the wireless signal would disconnect randomly.
Yesterday I bought a Dual Band Gigabit WiFi router ( Netgear R6250 ). This is now broadcasting on the 5ghz band for most of our computers and will automatically switch to 2.4 ghz for older machines or devices.
I now have a stable 47mb service throughout the whole house. No dropouts and a great user interface.
So my conclusion is that the Shaw router DPC 3825 is the problem and is just very bad at broadcasting WiFi around the house.
Shaw should provide a decent Dual Band Router to customers so they can really take advantage of the high speeds they offer.