Not seeing anyone else mention this problem so perhaps I'm an edge case but I have a 3 month old Macbook Pro (work supplied, fortunately) and I'm getting double presses on certain keys. I've managed to ameliorate it a bit with software [0] but it's still a disgrace that this is happening on a $4K machine.
I've had a 13" MBP with Touch Bar since December 2016 and have had keys that felt weird, keys that repeated, keys that didn't work unless you pressed really hard, and keys that didn't work no matter how hard you pressed them.
I've had the top case replaced for free two times under warranty, and the extended 4-year warranty does make me slighty less worried. The battery is also replaced as part of the top case which is a pretty nice bonus.
Though it is still a major inconvenience to be without my main computer for a week while it's being repaired.
Mine started after probably 8 months. I ignored it until it became work stopping (I decided against installing software to compensate) and had it replaced under warranty. Soon after getting it back I got a keyboard cover which seems to be doing its job. I hate accessories, and am really disappointed they released a new mbp in this same form-factor.
[0] - https://unshaky.nestederror.com/