Hmm
Well Honestly...
Poutine is best as most quebecois I know, with what is a somewhat slight bbq tasting chicken gravy.. its not sweet nor too spicy. St huebert does an OK job of selling a package version, however Pizzareia steves in Stanstead is good with theirs much like the IGA in the same town. I have found that St hueberts and some chalet swiss in quebec do an ok job. Mostly however , local joints in the eastern townships , as the Montrealers call them, do the best.
Dont be fooled. Most places in Montreal, while serving decent smoked beef(meat), dont do poutine justice.
Cheese curd is the ONLY way to go.. Even mild cheddar sucks. Ive made enough cheese to vouch for that.

You can make the fries thicker, thinner or even from a bag with McCains( Ore_Ida for those in the states)
The Gravy matters, as does the cheese.. I fyou want fancy versions with Muchrooms.. sure go to Montreal.. But really, Its not Poutine...
Which BTW is Pronounced Poo-tsein or poots-in
Poo-teen is the english way they pronouce it. Even a person from Northen New England knows Poo - teen doesnt work