But I have a T410 at home and I am not very happy with it. The dock is unstable, it disconnects, USB dies. The stupid dock blocks the fan, and you do anything cpu intensive and it end shutting the system down because of temperature. The NVIDIA graphics never worked reliably with nouveau + dock + suspend (I have to use the binary driver).
And worse, it is an i7 (x220 is an i5) and it feels so slow compared to the x220.