As someone who has had almost every thinkpad for the last 8 years. The newer ones are usually the low voltage weak cpu, hard to upgrade, awful keyboards/touchpads. The t410s has a small battery, non standard hard drive and only 8gb ram. If you go up to even the t420 you get 16gb ram max, msata/regular 2.5/and ultrabay. Sandy Bridge is a huge jump in performance and cooling, and battery consumption, plus you can get 9 cell extended battery.
They can be had for very cheap. I prefer the t420 to the t440 or t440s and the performance is actually better on the t420 imo, coupled with a superior keyboard/trackpoint, upgradeablity. There are even 1080p mods and quad core cpu mods you can do.