Cross Trainers For Sale Cross Trainers?

Cross trainers? - cross trainers for sale

Looking over a bus from the intersection with the goal to lose weight, buy - I noticed that there are various types of "resistance" and not knowing what each of them. There are:
a) Resistance to electromagnetic
b) the magnetic resistance
c) The manual resistance adjustment

Cross-trainer, I think the purchase is an electro-magnetic, but what is and is better than the other 2 options?

If it helps - I'm burning on the search for work half an hour almost every night a few calories ...

Thank you, all information would be appreciated.