I don't know about anyone else, but I wanted to get the Motocare accident protection warranty on a GSM dev edition (I'm rather clumsy). There was one thing I wasn't certain about though - the website says that the (standard) warranty won't become void if the bootloader is unlocked, but I saw no mention of whether or not it would void the Motocare one. So, I took to the chats:

Hilaree: Hi, my name is Hilaree. How may I help you?
Josh: Hi, I was wondering if the motocare accident protection plan was available for moto x gsm developer edition?
Hilaree: Yes it is
Josh: OK. The website says that unlocking the bootloader on the dev edition will not void the warranty. Does unlocking the bootloader void the motocare warranty?
Hilaree: No it does not
Josh: Ok thanks a lot!

So according to "Hilaree" you can still unlock the bootloader and the ESP will not become void. Whether or not that's actually true I don't know, but at least if something goes wrong I'll have the conversation to back myself up.