I use Ubuntu on a HP EliteBook Folio 1040. It's relatively nice hardware. The touchpad cannot really do middle click, but I always use external mouse, so I don't care.
I am sure ThinkPad T440s would be a nice machine, too.
I tried T440s exactly for 3 days and sent it back! Lenovo just screwed their trackpoint/trackpad experience (and part of keyboard as well). The virtual buttons do not work on Linux out of the box. Had to buy a refurbished T430s, with which I'm quite happy - only the battery time is really bad, I get just 2 hours on Linux.
I use Ubuntu on a HP EliteBook Folio 1040. It's relatively nice hardware. The touchpad cannot really do middle click, but I always use external mouse, so I don't care.
I am sure ThinkPad T440s would be a nice machine, too.