depending on the spring tension on it, it should be good at applying more pressure to the windscreen, moreso its cosmetic and not necessarily practicality.
To swap it though, you basically pop one off and pop the new one on! you may find it helpful to buy a wiper removal tool (also known as a battery terminal puller) dont waste your time buying the screw top one, you want to buy the two arm style with a bar
as these ones: are useless!
they can often look worse than they actually are!
By the looks of it, there is alot more plastic than standard. Would this mean, when driving at speed, the wind will be more likely to catch it when you try wipe the window and affect its wiping capability?
Just seen the seller, they are only up the road from me. they do alot with led lights.