Okay, im not from the US, so I maybe om not that into the word. But I use some of the same expression myself.

1. Car is not fuel efficient, especially not compared to econoboxes from EU.
2. It has luxuries. dual zone zlimate, key-less entry, leather/alcantara seats, xenons....
3. Not boxy
4. More expensive than what I consider an econobox

Extras:
Econoboxes are made to get people from one place to another. The twins are a sporty car, purposely built for sporty driving. (no fuel efficient turbo engine either)
Its not really supposed to have that many luxuries. Because it should be lightweight (but still it have some).
Its not supposed to be large. Again sportscar, shoul be small. Lotus elise is not an econobox, even tough its smaller and have less equipment.
Econoboxes are not made for performance
Econoboxes are often the cheap base model. In many cases the top-performance version is defined as a hot hatch. The twins compete with hot-hatches, not econoboxes.

From my point of view, its quite clear the twins can not be considered econoboxes.

Its all relative to other cars and economy.
If the car would only cost 50.000 USD i would be all over it. But its 80.000 USD here so... not really a bargain.

My whole econbox reference was to the lad who said the interior feels like an "econbox". Obviously the car is not an "econbox", but its not designed to have a good interior or features that make you go WOW. Its designed to be light, simple, rwd, 4 seater, somewhat economical (subjective) sporty coupe

Here's one for the Koreans


http://youtu.be/9bZkp7q19f0

Thanks for taking the time to translate this!! Enjoyed it 100%

0-8:30 hmm?
8:30~ Numnumnum
10:30~ OMFG

Thumbs up!