They are godawful to take apart and repair though. The X220's and X230's aren't bad, but they've been plagued with difficulties (X220 has >3% failure rate on the displays, Lenovo just shipped 650 or so X230's as part of a recall for multiple issues). I just assumed that the X220's had a bad crop of panels from their supplier, and the X230 was brought to market too quickly (they should have caught all the obvious problems that affected 90+% of their laptops before production. In our test sample, 2 or 64 were okay)
There's really no reason to use that may different types of screw in a laptop ever. It may add stability, but the routing of cards and cables in the magnesium inner frame just begs for failure. I've replaced too many where the cable has been severed internally because the edge wasn't beveled enough, or where the WIFI card standoff has broken, and has damaged other components. It can get ugly. Some of the internal connectors are really trustworthy, and excellent, some rely on tape to maintain the connection, and those can fail to frequently.
Thinkpads have always been a mixed bag for me. Like apple, there are some things that are implemented really well, and some things that are poorly done, and some things that aren't bad per se, but are dealbreakers for me.