Sorry, I've been out of town (& away from computers) visiting family in recent weeks. Still catchin' up on some old threads.
"Best contact places for dances?"
In downtown Montreal, I'd suggest Caleche Du Sexe, Club Downtown, Club Super Contact (if you happen to get desperate), Kamasutra Club, Kingdom Gentleman's Club (later at night - past 10 PM for sure), and Le Gentlemen's Choice II (formerly called L'Axe).
"Best places for extras?"
In downtown Montreal, you will almost certainly be out of luck in this area at strip clubs, but the escort scene is HUGE in Montreal & basically legal. Pay cash & ask for exactly what you want upfront at all times.
"From what I gather, and correct me if my perceptions are incorrect, it seems you need to leave the city itself if looking for extras."
This is correct. Some off-Montreal-island strip clubs that I can recommend are Hill Top & Bar Le Gentleman...and, if you feel like a longer drive for some reason, Chez Diane and/or Club Frontiere.
"Also, based on my personal preference, I find non-contact places generally worthless, so a list of places to avoid would be much appreciated."
OK then, Bar Rendez-Vous Erotica has appeared to be closed the last few times that I drove by it, and Bar T.D. Spectacle is pretty much a rat hole IMHO. Also, Club Super Sexe is a downtown tourist trap, and the contact is very, very poor at Chez Paree, Club Wandas, and Bar Salon Le Vegas. Cabaret Sex Appeal is also a rat hole IMO. Studio d'Exhibition Pussy Corps isn't really a strip club per se, but you might get an "extra" there at your own risk & for a high price. Temptations (formerly the Chateau du Sexe) has had some gang trouble in recent months & might not even be open at this point.
In general, the farther away from the downtown Montreal region that you get while still on Montreal island, the more likely you will run into a mostly French-speaking environment (like at Bar Sexe Mania or Cabaret Bazaz). There's also really no reason to drive all the way out to Ste. Hyacinthe or Saint-Mathieu-de-Laprairie IMO, and I would avoid the Miss Dorion if possible.
Bonne chance! :)
Oh, and avoid the Internet Trolls on here at all cost...lol...