Personal, I'm not a fan of Nostalgia Electric. I had the smaller 4oz model and it didn't even last a year. The problem I had was purely mechanical, to the point that it seemed like a pretty big design flaw.
If I remember correctly, the agitator that spun within the kettle was not directly connected to the motor. It engaged with a gear when the kettle was in the popping position. The problem was that the only thing that held the gears together was the weight of the kettle. So when the kettle would begin filling with popcorn and the agitator would get the tiniest bit of resistance, the kettle would kick out a bit and the gear would skip.
This happened occasionally at first, and then began happening so often that it would just stop spinning and the popcorn would burn into a congealed mess on a regular basis. I began creating home-made wedges to hold the kettle in place, but that was just a band-aid and never solved the problem completely
For $90, I'd have almost said, "go for it", but even at $90, (unless theyve changed the mechanics) I find the quality really poor.
For $200+, I'd suggest a paragon. I upgraded soon after I grew frustrated with my Nostalgia unit, and I've been very happy with it.