If this is your first handgun, is warranty the true determining factor? Like others have said, most restricts in Canada are in much better condition then their counterpart in the US because our hand guns are primarily range toys. A Beretta 92 for example is a pretty robust design and chances are, a use one (not the LEO trade in ones) will be in good shape. As for warrenty, like others have mentioned, it does not existent in Canada so why not save yourself a few dollars and buy used!?!
The bigger question, is that for your first handgun, one that will posibly keep forever, will your personality tolerate the little scratches, dings and ware marks that is enharent to buying used? I have bought used handguns that are exceptional shooters but with holster ware and I have always said to myself that I should have bought a nicer example. On the flip side, I have also bought expensive pistols that I wish I bought used because they are such bad shooters that a couple of scratches would not bother me.
In the end, I said do your research and buy a good design. Really consider buying new if it is your first handgun because it is the one that you might keep forever or pass down to family. Less chances of something going wrong when buying new, both with the gun and the transaction. Every other handgun after your first purchase could be used. As for the warrenty, sucking in Canada, it is true but chose your store wisely because there are a couple of businesses out there that has a customer service satisfaction guarantee that is up and above the manufacture warrenty. I have a 2 year old 22/45 with a bulged barrel that got switched out, no questioned asked and a one year old pistol that was replaced with a new one, no questioned asked because it wouldn't lock open. I continued shooting it up to the day the transfer for the new one came through. Pick you gun and gun store wisely, even when buying new. Good luck.