The very first thing you need to do is decide what your goals are: do you want to improve your stamina, cut down those love handles or give your body a definition ? For each one of those goals, you could purchase a different elliptical trainer for optimal results.
For example, if you want to lose some weight, you could buy a cheap elliptical trainer that will be used for that purpose only and then get sent on a prolonged vacation.
For a second goal - improving your stamina - you should be after an elliptical trainer that will endure in time.
And for a third option, if you are after building some mean lean muscles on your body, you will need to get a machine that can sustain heavy and intense usage.
So, as you can see, it's up to you to decide what you're aiming at, and then choose the right elliptical trainer from an appropriate category.
To be continued.