120GB is low, but not nearly as low as other limits I've heard of.
I'm in Halifax, and the ISPs here seem pretty decent. Bell Aliant doesn't have caps at all - they used to be a distinct entity from Bell, IIRC, and are still sort of separate from the Bell that's often mentioned - and Eastlink caps at 250GB, or were planning to a few months ago anyway, but that's only for their 50 and 100 Mbps plans. The normal, standard-in-a-bundle plan is 20Mbps and is uncapped. I've been pretty pleased.