Migrate SCM System 4.0 to NW 7.0 Release

[olli2003]

Hello Gys,
can anybody give some recommendations to me, how it's the best to migrate an old SCM 4.0 Release to NW?

There are some differents opinions to do so:

1. First to mirgrate to the lowest uprade level 4.1 and in a second step to the NW instance.

2. First to mirgrate to the latest upgrade level 5.0 (5.1) and after this to 7.0?

Does anybody know what are the differents between this two possibilities? (f. ex. of the relative downtime, workarounds in the SAP base or in customizing the SCM specifics applications)
Have anybody expirience in such a migration like ours?

Thanks for all ideas and suggestions,

Kind Regards
Oliver