My favourite deck is Monarchs Playing Cards, specially the Red and Purple editions... In my opinion, Monarchs is the first deck which has and elite quality for magic and cardistry because they feel really smooth and comfortable for any manipulation...
I love Ellusionist’s Cohorts, because they look like a normal poker deck, and nobody suspects markings or gaffs. Also, Daniel Madison’s Pink Bangers make me emotional just looking at them. Chef’s kiss!
My favorite deck ever is "Room 237" by penguin magic. Due to the extremely limited run that it had and "The Shining" being one of my favorite movies of all time.
Navigators, personally for combining sailing with cards (a lot of card playing after dropping anchor), design-wise for the the simple Captains wheel back, custom Aces, Courts and Jokers. Also appreciate the double-backer.