Since I came from Acrobat I keep getting asked if it's a replacement, so here's the unsentimental version.
Acrobat is a tank. Twenty years of features, forms, redaction, prepress, the works. If your job needs all of that, it's not going anywhere. But its actual text editing is box-overlay, you're shoving fixed text frames around and the moment you add a line everything stops fitting. ReflowPDF's whole point is the opposite, the content reflows, so editing a paragraph feels like editing a document instead of defusing a bomb.
Where it loses to Acrobat right now: it's newer and smaller, so there are corners that just aren't built yet. I'm not doing complex form work here. But for the 90% of my week that's 'change this copy and re-export clean', I haven't opened Acrobat since. And $10 vs whatever Adobe charges now is not a close call.