The NES Classic is just pure nostalgia in and adorable little form factor. It transports me back to being 5-10 years old again and I can't describe the joy I get from seeing my kids play it. They're just so happy playing the same games I was at their age. It's amazing.
If you have any nostalgia for the NES you should pick up a Classic as soon as they get their stock situation under control. You won't regret it.