Have you tried a windscreen coating - they can be quite effective above say 30 mph and you don't need to use the wipers then.
I do agree though, the wipers aren't the best.. my old S1 wasn't too bad they did seem to wipe ok and not obliterate themselves or anything else - but not yet tried the GTN ones. I bought replacements wipers from Morgan which cost a fortune. They do however look very similar to original Mini ones.
