Minecraft 1.8.1 crashes on startup

Not sure if these are in order, but there are about to be 3 bug reports from me. Basically I had the latest Faithful 32 texture pack installed, and switched from that to PureBDCraft 512x. And... it crashed.

I expected it to actually work!

...It didn't.

Steps to Reproduce:
1. Connect to an MCProHosting server
2. Change to Tiny Pixels Texture Pack
3. Change to Faithful 32x
4. Change to PureBDCraft 512x
5. Cry hysterically when MC crashes