With me keep the Aerotwin usually almost 2 years .... then they start very greasing or "chatter" on the windshield.
Important for the life but also the care or the handling. I clean my wiper approximately once a month with window cleaner and a soft cloth. What there every time on dirt coming down ... incredible. Likewise, the wipers are always folded up in the winter. The freeze is just about the most harmful for the wipers.
About the then relatively good life, the high purchase price into perspective (especially the EIA Bosch is beyond good and evil).
This product can only recommend therefore .... for years driving the Aerotwin forward to my vehicles.