I've several Glencairn whiskey glasses without the below product (i.e. tasting top). Do you use this product and does it contribute to the smell, taste etc.?
http://www.kiltswihae.co.uk/glencairn-w ... 5759-p.asp
PS. There are two caveats which may affect your comments:
1) After I pour the whiskey I rest in the glass for about 30 minutes.
2) I will be using the product for not only drinking a single whiskey, but also, from time to time, for comparing different whiskies.