Ah yes, that's right. Sorry, I forgot the 505 was the smaller version of the 510, which I'm sure doesn't have the issues they're talking about. I bet they're all trying to use it on glass or something

Yeah, I tend to ignore product dimensions on Amazon, unfortunately. I don't have a clue where they draw this information from, but it seems like half the time (as it clearly is in the case you provided) the dimensions are actually the size of the product packaging, and not the product its self. I've seen the product on store shelves and that's about the size of it.

Anyway, I'm glad you got a mouse you like. I know how it is, we really get accustomed to our mice, I think. I used the same mouse for about 8 years before getting the one I have now, and it took me a good 6-8 months before it felt right. And that was with a small difference in ergonomics.