My answer is probably not representative but I adquired a new display for a ThinkCentre M55 two years ago: a ThinkVision L197 (model 4434-HE1). The monitor arrived dead, it did not power on. Called Lenovo's technical service (same as IBM's at least in Spain) the same day, and they sent a replacement unit. However, replacement monitor was an used one (and in a very poor condition, with some obvious damage on the case, packaged on an old generic box). After calling Lenovo again, they said that when a replacement unit is sent they do not know if it is a new or a used one and there is nothing they will do about it.
Of course I returned the replacement unit and fixed electrical problems on the L197 myself. While here I fixed ten dead pixels on the LCD display too. This monitor is working fine now and the display quality has improved a lot.
I am sure other customers will have more pleasant experiences to share.
ThinkCentre M55 (8808-94G) - 2GB RAM, 80GB HDD; OpenBSD/amd64
ThinkPad T43 (2668-6CU, 2668-W4M) - 2GB RAM, 100GB HDD, NMB (US); OpenBSD/i386
ThinkPad X40 (2386-E9U) - 1.25GB RAM, 80GB HDD, NMB (US); OpenBSD/i386
ThinkPad T430s (2353-2MU) - 16GB RAM, 128GB SSD; OpenBSD/amd64