I have a Miller Dynasty 200, which I think is only a little out of your price range (it was for me as well, but I still got it). It is a good all around machine: will plug in to 110, 220, 460V single or three phase, does not pull too many amps (my previous machine tripped my breaker all the time), it puts out 200 amps which is enough to do aluminum thicknesses used for car fabrication (at 165A, that Econotig will have a hard time getting penetration into anything thicker than 1/8").
As far as not having a cooler, mine is rated 100% duty cycle at 200A--however I find the torch gets really hot after more than about 6 inches of continuous welding (but that is making a big bead at max capacity on 1/4"). It has not really been a problem for me because all my aluminum projects are small. Another thing to know is that air cooled torches are bigger than the water cooled ones, making them a little harder to manipulate and get into small areas--but the difference is not that much.
Hope this helps,
Mark