I've used and paid for Dropbox for well over a decade. Other than the rare hiccup every few years (usually due to switching machines/OSes or whatnot), it's been rock solid and a true workhorse. I know there are many other options, including iCloud Drive which I use sparingly, but Dropbox is a service I trust. I hope it continues in that manner and they don't destroy their reputation with a woebegone "pivot to AI".