I have a long fence row that gets a lot of blackberries and other fairly thick brambles along it-had the same problems you are, mostly because I just want to cut it once or twice a year, and the growth gets really thick with that degree of laziness. I looked at several walk behind trimmers, finally bought an Ariens. It's a great piece of equipment, very reliable-my only criticism is that the factory supplied strings are not durable enough. Solved this by buying another manufacturers heaviest duty stings and putting them on the Ariens. Other units were a lot more expensive, I think I paid about $320.00 for mine.
