I am a firm believer in proper winter tires, as they have a huge safety advantage compared to regular a/s in Calgary, my family will never go a winter w/o proper winter tires.
As far as studs, well I have a differing opinion.
Studs on a proper winter tire (ie. have the snowflake on the sidewall), are a waste of money. They are not doing anything at all. Today's winter tire technology is very advanced and a studless winter tire will be just as safe (if not safer)than a legally studded winter tire. The best winter tires out there have tons of sipes, soft compound, and good spacing between the blocks to clear snow. Hakka's are hands down the best winter tire out there, that money can buy, and yes they are expensive.
Studs on a M&S tire will help, but getting those tires siped will help more.
The problem with studs, is they do nothing on black ice. What causes the most accidents? Black Ice.
Hell, I'll even bring in the Rally references.. Last 2 years in a row, Big White Rally (out in Big White Resort in Dec.), all of the top teams ran studless tires (yoko A034's). We've been there running course opening both years, and let me tell you there was alot of snow & ice covering the stages. These teams take rallying very seriously, they have the ability to cut, groove, sipe & stud on site. Very few decided to runs studs because the amount & size of legally allow studs doesn't warrant it.
FYI, those tires up there are ice racing tires not rally tires..
This is a proper studded rally tire
Which BTW is not road legal in Canada. These studs are too large, and stick out too far.