Not even if they could last six years or more? That's how long the original wiper blades have been in service on my 335xi: Six years, 108,000 miles and still cleaning perfectly with no streaks or smears. This past winter was the first time they began to chatter or skip, indicating they have stiffened up at last and will need replacement before the cold weather returns.
Often the inserts don't actually need to be replaced, just cleaned. Once or twice a year, I clean off the oxidized rubber using paper towels and household ammonia. It's also important to keep the windshield scrupulously clean (and therefore, smooth--I clay-bar the glass annually with the rest of the car [and use Rain-X when I think of it]). With that little bit of extra care, wiper inserts/blades last a ridiculously long time.
(I wouldn't expect that kind of life in the blazing heat of the Southwest, though. Here in the Northeast, they'll last much longer than 1-2 years with proper care.)