I'd tend to agree with the good Doctor, mechanically the hand- propelled machine has less moving parts and should last forever- my father had a Briggs & Stratton machine that went for 14 years before it was retired. The most important thing to consider when buying a lawnmower is the deck of the machine. Go for an alloy or composite deck which will resist corrosion and is easier to clean. A pressed steel deck is light but will start to corrode pretty early on. You'll probably need to spend about €300 though to get a machine with an alloy deck.