If you enable Developer Mode and load unpacked extensions on Windows, it complains about it every time you start Chrome. I'd call that a (major) inconvenience.
Yeah it shows a tiny little balloon-tip style thing over the hamburger menu.
I was going to say it's not a big deal but I quite distinctly remember it being the entire reason I switched to Vivaldi instead of Chrome. Full extension store compatibility with none of the nagging, and all the other cool shit it does is just a bonus at this point.
It does. You can pay 5 bucks to get a dev account on the play store and then upload your extension there (unlisted if you want), and install it from there, and you won't get the nag popup