"Have been using it for nearly six months, I am still impressed by its light weight and good performance. The material it uses makes it lighter and thinner, however, also make it not that sturdy as a cost. When pressing the border below the keyboard, I will feel a little bit frail, especially round the left lower corner. Another problem is the touch pad, that is really a not a good design I think, when pressing the touch pad, it will make noise. I tried my friend's Thinkpad X1, the touch pad on it works quietly and very well. There will never be a computer satisfies everybody, but in general, this one is a very good one."
"If you move the mouse by trackpoint, then you have to physically click the touchpad. Clicking the touchpad requires much more strength than the separate buttons, and the required strength is more than your thumb can be expected to provide without provoking a good case for Repetitive Strain Injury (RSI). You hands, especially your thumbs, get tired very fast from clicking the touchpad when using the trackpoint for mouse movements, and that makes RSI a very obvious result."
Cons: Wireless card, upgradability, not future proof
"I've been relatively happy with my t431s but today I have found with huge disappointment that Lenovo prevents (through an hardware whitelist in the BIOS) to upgrade the Wireless LAN card in this and most other Thinkpads. It seems absolutely ridiculous to me that Lenovo would just disallow me to switch to a wireless AC card, especially when I'm just trying to go from the Intel 6235 that came with the laptop to an almost identical Intel 7260. So should I buy a new laptop just to enjoy faster backups to my NAS? This is quite a shame and reason for me to lower my overall rating from 4 to 2 stars. Lenovo please release a new BIOS that allows AC cards to be used.. I have purchased this machine and it's my right to keep it up to date with good, reliable hardware upgrades!!"
Pros: Weight, Processor, low noise, long battery life
Cons: Keyboard/peripherals, Screen size, clickpad
"I own a t400s and recently bought a t431s. Both run under Linux. A big plus of the t431s is its low power consumption (ca 8W vs 12W under light use) and consequently long battery life. Moreover, it's very quiet and the screen has visibly better contrast if gamma-corrected (gamma=0.8).
The clickpad on the t431s is a step backward --- it's difficult to use and makes more noise than the dedicated buttons on the t400s. Another concern is the missing capslock LED and the F-key labels, which are difficult to read.
The 16:9 screen size of the t431s noticeably reduces the usable vertical display size, even though there are 900 pixels in this direction (the same as on my t400s). The pixels are about 10% smaller so that letters come out smaller or, when scaled, occupy more vertical space."