I wrote a tool to convert between all of the RSA key formats that I could find: http://github.com/jpf/lokey

If you're still curious if the key material is different (I'm very curious), try the following and compare the results:

    pkcs15-tool --read-ssh-key 1 | lokey to jwk

    pkcs15-tool --read-ssh-key 1 --rfc4716 | lokey to jwk

(You can also replace "jwk" with any of the other supported RSA types. It might be easier to compare the "ssh" type)