Lawn Sweeper/Vacuum.
 

I am looking into purchasing a lawn sweeper/vacuum, not the ones that
are carried on your shoulder but one of the four wheeled ones you push
around (like the billy goat).
We have a few trees in the garden, pine & horse chestnut.
What are these sweepers like at picking up fir cones & twigs ?
How often to the bags require emptying ?
The local garden centre have an Alko in stock which I quite liked the
look of, any opinions/experience on the subject would be gratefully
received.
Regards,
Andy C.