Is it rude to ask the dealer too many questions when buying new?

[Northernraider]

None taken, but I really cant imagine a manufacturer supplying wheels with such a tight margin that a 10% increase in weight takes them out of spec

Hmm I don't know I mean 10% is 350kg

Now. When I buy shocks for my hymer which is a fiat ducato you get ones that do up to 1500kg and ones that do 1850kg
So what if the alloys are rated the same way. Stranger things have happened