Upgraded to Shaw 150 today....
... but after enabling passthrough to my Linksys RT-N16 router running Tomato DD-WRT, the download speed maxes out at 130 Mbps every time.
Looking into it, it looks like this might be getting into speed territory that Tomato compatible routers can't handle (when running Tomato). If there's anyone that keeps up with the Tomato developments and knows of a Tomato compatible router that can handle faster speeds, please share.