Getting weeds out - without chemicals or expensive labor

We just purchased this device to remove weeds in tree wells and in sidewalks - with the rains upon us, weeds will be popping up everywhere, and we were looking for a fast, efficient and pesticide free way to remove them. This looks like it's just the ticket:

http://www.amazon.com/gp/product/B00004Z2FP?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00