My mother bought some windsheild wipers - I think they were 'triple edge' or some other nonsense.
Anyway, they promised a 28 day warranty - but the instructions warned that they may need 2-3 months to 'bed in'.
We put them on and they were crap - really bad, but better than the 2 year old stock wipers. She persevered. By the time we got to 2months, they were completely worn out and useless - squealing, jumping, smearing - and by then, they had carved some lovely deep scratches into the glass.