I can't speak to the FAQ, I guess by 'gigantic' they mean tens of GBs. I use it for what i consider large files all the time, I just opened a 2GB file to check

I can't speak to the FAQ, I guess by 'gigantic' they mean tens of GBs. I use it for what i consider large files all the time, I just opened a 2GB file to check I am not going mad and it worked just fine. It took around 10 seconds to open so I agree it's not the quickest to start but at least it does. I'm running Textadept 10.7 on a decent Linux machine.