Don't run in v8086 mode unless you have to (BIOS boot in Intel VMX). Just go directly to PE or LME as the new docs tell you. It may be interesting to look at the history though.

Also, while devs have to write portable code -- don't bother. It'll save you a bunch of time if you just write the IA32e specific asm code.

If anyone has any interest, I can also post my adaptation of an asmx86 vim syntax file I hacked up from something I found on Stack Overflow. It's not that great, but it does at least fix some of the register highlighting.