/tpg/ Objective Model Guide

For freefags who don't mind a slower PC / need LibreBoot and willing to SPI flash:
T400 - 14", normal size
X200 - 12.5", ultra portable

For normal users who need the classic keyboard / need Coreboot and willing to SPI flash:
T420 - 14", normal size (will support Libreboot by 2018)
W520 - 15.6", takes a TN 1080p display
X220 - 12.5", ultra portable (will support Libreboot by 2018)

For users who like the new keyboard, or want to swap the classic one in:
T430 - 14", normal size
T530 - 15.6", slightly bigger, takes a TN 1080p display
X230 - 12.5", ultra portable (supports Coreboot)

For users who like the modern style and the new touchpad, or want to swap it out:
T440p - 14", normal size, beautiful FHD IPS display, no downsides (except Classic Keyboard), takes Intel 7260 ac+BT without whitelist
T540p/W540 - 15.6" / 15.5", slightly bigger, takes a 15.5" 3K IPS display, takes Intel 7260 ac+BT without whitelist

The X240 is NOT recommended because it only takes a single RAM stick, which degrades iGPU performance, though it takes an FHD IPS display.

The T440 is NOT recommended because it has no real performance gains over the T430 (only better battery), and does NOT take an FHD IPS display.

All xx30 models will not take an AC network card without doing an SPI flash of a modified BIOS.
All pre-xx30 models will not take an AC network card without a software BIOS flash.
All xx40 models take the Intel 7260 ac+BT.

Instructions for SPI flashing are here: https://libreboot.org/docs/install/rpi_setup.html
The pinouts and procedure are the same for all ThinkPads (confirmed and tested), but lookup your chip model for the flashing part (replace -c "MX25L1605" with your model).