I have a T430s as my work computer, and it's great. Not the best battery life, but the weight and size are excellent. The only problem we've seen with the T430s laptops is that if you have particularly heavy wrists, some of ours are showing case cracking on the front corners.
Although the current generation T440s has better battery life, they screwed up (IMO) the trackpad. They ditched the discrete mouse buttons, and now the whole trackpad clicks. Which is fine if you do it right - but Lenovo's actually "sinks" noticeably when you click it, which is incredibly awkward to use.
As far as the M93p towers, we use those as well. They're good, but definitely opt for an SSD in them. The difference is night and day. We've had very few repairs from our fleet of M91p, M92p, and now M93p towers.