The only downside of mIRC's built-in split feature is that it doesn't come with tags, which makes it kind of hard to use a merge script to merge them back together
To the original poster: If you want to know where your messages are split off, there are plenty of custom split scripts out there that do show the split to yourself as well. Be sure to disable mIRC's built-in split feature if you use a custom script, or your message might split twice.
