Even after the honeymoon phase, it's still rewarding.
Pros
Ecobee wouldn't be what it is without the people that make it. Every person I've worked with, reported to and collaborated with has been receptive to new ideas and have no problem helping you out for the greater good. The vision of the company is clear and is made better by the people who come in and work their butts off every day to deliver that vision. This may seem a little dramatic, but I'm lucky and proud to say I work here. I never feel like going into work is this struggle as my role, management and surroundings is challenging and rewarding.
Cons
As with most growing tech companies, there are growing pains. Some minor flaws (that I can see from my department) is primarily communication and standardizing how departments work with each other. Structure is still coming into it's own and will find it's way eventually.