Just for reference, my noname aftermarket 6x16" winter wheels are also 10 kg each!
If you want lightweight performance, it is better to go for a slightly smaller wheel than the ones your are discussion in this thread. 7.5x17 would probably work well on the one series. Some people think that smaller wheels have taller tyres which would compensate for the saved weight, but those kinds of tyres are actually lighter than the ones that fit the huge rims.
And stay away from runflats. They are really heavy.