The good news is tires are much cheaper overall today then few years back so winters are much more affordable.
Michelin X-Ice 3 is the best winter tire in my opinion (for GTA) and I think the only winter tire on the market right now that actually has a mileage warranty.
I would also consider Bridgestone Blizzak WS-80 (it is a brand new design, just came out) or DM-V1 (for SUVs and trucks).
Nokian makes good winters, they invented them, however they are a much smaller company and I don't believe they spend the same kind of money on research and design as the big boys on all of their products, nevertheless, a great option with their Hakkapellitta line.
The above 3 companies are generally considered the cream of the crop. You don't believe me, search around. You'll see them popplng up on almost any kind of a list.
Pirelli and Dunlop have decent offerings as well, with their premium lines.
Toyo, Yokohama, BFG and Continental are brands I would look at if I needed to find a bargain price.
General Altimax is nowhere near close to the levels of performance Michelin, Nokian (with their top line) or Bridgestone offer.
It's a decent tire but a different ballpark. I'd still buy it ahead of a Goodyear or Firestone.
Someone mentioned Blizzak WS-60 as not being the greatest - true - however that was discontinued many years ago and doesn't represent the current state of affairs at Bridgestone.
WS-70 were a huge improvement and now they are also gone so we're talking 2 generations of tires ago.
It is also important to realize, that in the city we mostly deal with ice, slush or even dry pavement - not so much heavy snow. Get a tire that is optimized for those conditions if you live in an urban setting. Many manufacturers designate different tires for different type of vehicles, most notably passenger, SUV and LT, and performance. So that's yet another factor.
A thing to remember - great wear doesn't always mean that the tire is good - quite often it means that it has been optimized for dry winter driving or simply that the rubber compounds are too stiff (often the case with cheap tires and low end manufacturers). People praise them for great tread life without realizing that the performance they're getting is probably just a bit better than your average all-season.
Finally, despite all that, almost any "winter only" designated tire will outperform an all-season or a summer tire during the cold season. So yes, it's definitely worth it.
As for TPMS - it's not a law to have them in Canada so you guys don't need to spend the money. However, the cost went down and you can find them for 40 bucks a pop, brand new. They have a life of around 10 years on average, btw.
OP - if you like your Michelin Primacy MXV4 all seasons then replace them with Michelin Premier A/S when the time comes.