Except for the brass radiator, brass trim on head/cowl/tail lights, hood, fenders and hood former on cowl they are pretty much the same car. There are a lot of fake 1915 built from later cars (17-22) so you should do a little research before you jump on it. It is said there are more 1915's then what was built by Ford at the factory.
Low cost car that gets you into the HCCA.