I'd choose a mouse over a trackpad (I have the Logitech M705), but trackpads can be really good in some cases too. Maybe I'm a bit biased toward trackpads since I'm on a Mac, which has the best trackpad in the market. The thing with trackpads is that they have so many gestures, but they get rly uncomfortable after some time. The ergonomic shape of mice make it easy to use for long periods of time. When I'm on my desk, I use mouse and when I'm not, I don't really have any problem with my trackpad. What do you use?