[Klathmon]

find/replace works fine, and it's an XML file so syntax highlighting is working great (although it does take a few hundred ms to actually apply the syntax highlighting after a lot of scrolling)

It did take about 2 seconds to load the file though, so you can make fun of that!

[kedean]

On a more constructive note, I've found that it does have significant problems with certain text structures, namely really long single lines.

Just the other day I had to debug a json serializer, so my q&d solution was to copy the text out of the eclipse debugger, paste it into Atom (as it was already open), then find my way to the section I was looking for. After significant delays getting to the spot I needed with 'find', any use of the left and right arrows to navigate the text further was accompanied by a ~5 second delay per character. The same operation in Notepad++ went smooth as butter.

[Klathmon]

I agree 100%

I'm not sure specifically what it is, but it seems longer lines just wreck the performance.

I've seen a few commits talking about fixing specific problems that have caused this in the past, leaving me to think that it's most likely either one or more of my plugins causing the issue, but i just haven't cared enough to look into it yet.

Just like you I keep Notepad++ around for my "quick" needs (open a file for less than a minute) and for big files that aren't "code-ish" (they have long lines), and then atom is used for everything else.