I have a 1st gen Firestick, its in the bedroom so don't use it very often. I find it takes a long time to load (well, longer than other devices) and then its like you click a button and then there is a delay between pressing and it doing anything. Once the app is loaded that I wish to use it's fine, it's just the initial start up that annoys me, I'm just impatient.
I did buy a 2nd gen which was a lot better, but I sent it back as I decided to upgrade to an Nvidia Shield.
I used to have a Fire TV box as well, they were good, a lot better than the stick IMHO, much faster etc, I only got rid of that as I bought an E2 box.