I prefer using a Trackpad, however the Thinkpads have a middle button, which I use all the time in Linux.
I think by default hitting the left and right mouse buttons in linux emulates a middle click. You can also configure three finger clicks as a middle click, which is my preference.
The XPS touchpad is comparable to Macbook one, you won't miss the track point.
I was forced to use a Mac for one of my job ; didn't get converted to the touchpad!