Replying to myself as an update here, for the benefit of others.
It's been 7 months since installing the Ali-Exp wiper blades, and to be honest they're already done. They were great at first - quiet, clean, did all you want a wiper to do. I've been doing my usual of giving the blades a quick wipe with a cloth once a week or so (any time I reckon I'm going to get in the car and pull the spray/clean), but about a month ago they got really noisy.
After coming back from a few weeks on holiday, my first wipe yesterday was bloody awful.
I've cleaned the windscreen properly, and the blades, but they're still very streaky, and the passenger side won't sit probably on the windscreen any more, just skips a large portion left-of-centre of the hook.
Time to try and find the Bosch on special, or grab another set of Tridon rubbers, which for $18 lasted two years previously.