I'm not selling the things, but "slightly" seems to be a strange word to use here.
I'm only going on the table you linked to but the 580EX & EXII improve from 31 metres to 52 metres in the EU, the 430EXs from 12 to 31 metres.
Given that their advertised range is 240 metres and the non-RF producing flashes can do that, I'd hardly say the interference problems are solved, just slightly improved upon.





