Too bad about your rattle. What's your source that 1/2 the bikes have a rattle? Numerous reviews did not mention it. You'd think 1/2 the reviews would mention the rattle if 1/2 the bikes had it.About 1/2 the people with one complain of loud, annoying rattling noise in the middle of the RPM range.
When you talk to the dealers can you ask them what they say about it, and can they contact Honda to get the 'official' line on it before you buy it.
I've mine for 8 1/2 months now, with 14,000km on it, it's a great bike but if I could go back I think I would have gone for the ninja, it's simply a much better build and quality of bike.
Honda seem to have been ignoring the problem that 1/2 the bikes seem to suffer from, and I think will continue to until possible customers want clarification on what it is before they buy them.