It´s certainly a matter of taste which whisky glass you prefer: a tumbler or nosing glass.
A tumbler is often considered as the traditional whisky glass. I´d recommend to use it when you going to drink a whisky you already know or if you mix it (what I could never do). I love the tumbler because it feels good in my hand. So I choose it to the criteria of weight and tenuity of the glass.
While tasting a whisky for the first time I use a nosing glass. The tulip shape is ideal to swirl the whisky around without spilling it. The whisky aroma will be concentrated at the glasses edge. This will allow it to develop the whiskies full flavor.
Conclusion: A lot of whisky lovers make a fuss about the right whisky glass. The tumbler is a heavy glas which lies comfortably in the hand . The tulip shape of a nosing glass is perfect to define the whiskies taste. Just try it out and decide yourself which you prefer.