A 15"wheel and tyre and a 16" wheel and tyre are almost the same overall diameter and rolling circumference. The inch rim diameter difference is equalised because 15" tyres have slightly taller side walls than the equivalent 16". This is also why 15" can give a slightly more comfortable ride on rough roads and 16" slightly better handling. But ,like olduser, I run both sizes and dont notice much difference that couldnt also be explained by the difference in tyre brands.
There will be no clearance problems unless you go wild with non standard wider wheels or wider tyres, in which case you would probably also need to tell your insurance company.
But all else being equal check the prices and availability . Honda, like many Asian car makers , specify tyres sizes that are not the most common sizes used in Europe. Easy enough to find but I found more choice in 15" and up to £30 EACH cheaper for the same brand. (and some premium brands were not even made in 16")
