I am a Montrealer but I have been to both Wicked and OasisAqua Lounge recently. Wicked has a larger club area with the swing premises above on two floors. Oasis has two small bar/dance areas as well as the swing premises. Their rooms seem recently renovated and it has a great ambiance. Their spa facilities are outstanding. There is a steam room, sauna and hot tub and a nice sized outdoor heated pool.
My preference is for Oasis but Wicked is good as well. Of course I find with swing clubs it all depends on who you are with and the crowd that is there with you.