I can understand your reasons for getting small, light and simple
@Lowena, but at the end of the day, as I think somebody has said already, you get what your pay for. If you get there then spend the whole time having a tussle with it, especially if you have a machine at home that behaves beautifully, you will be, being polite, extremely angry. You are a highly competent sewer, you will always expect the same with your machines. Paying slightly more, with a heavier machine would be better, especially with it a trolley as suggested by
@Francesca.
I hate chucking money away, and IMO, that would be chucking money away.