I tried Sublime Text 2, loaded up a 150mb log file. It took over one minute to load, then crashed a few seconds later. I uninstalled it and am keeping Notepad++ and donating money to it.
One of the things I love about Sublime 2 is how it handles large files.
I just ran `cat /dev/urandom > test.log` for about 15 seconds to generate a 160MB file, and it's currently opening in the background with a nice smooth status bar in Sublime, using up a single yielding thread while remaining completely and entirely UI responsive while loading. You can cancel loading at any time by closing the file; this doesn't interrupt workflow or slow you down at all if you accidentally open a massive file (awesome).
It finished opening the entire 1.1 million (!) line file in about 2 minutes, followed by a brief 3 second delay, followed by displaying it perfectly in the editor. I could smoothly scroll through the whole file (as smooth as if it were 100 lines), even using the minimap that displays a small representation of the whole file. Memory usage jumped about 200 MB, but that's to be expected and is rather efficient considering the task.
I'm not a Sublime evangelist or anything, just saying my experience completely contradicts yours, to such a degree that I think of Sublime second when I want to open large files.
Why second? Well, because you should really be using command line tools for files that big anyway.
*edit: Almost forgot to delete that test file. Whew.
If you have a plugin that scans through every line in a file (yes, some are this stupid), a large file will take ages to load. Some syntax highlighters that use inefficient regexes have a similar problem, but with long lines.
You can test this by opening your giant file with `vim -u NONE large.txt`. That disables your .vimrc.
I just opened allCountries.txt[1] in ~36 seconds on my MBA and vim scrolls through the file smoothly. 8 256 007 lines taking up 960MB.
[1] http://download.geonames.org/export/dump/allCountries.zip