VPN question: Ext. and or int. managed gateway

[frankd]

CP NG R55
It seems to be possible to setup a VPN with a internally mgt gw while this gateway in reality is externaly mgt. ( Sic is not running)
I know this is not ok , but it works. ( for now ??)

1) Does it matter if new fw-objects are created as external or internally mgt ?
2) What is the difference when setting up new VPN's

While we have to migrate some ext. mgt gw to internal I wonder if I can create them already as internal mgt. So we can do the migration in step by step. Or will I face some problems here ???
The ext mgt. gw's are already in use by VPN's.

Hope to hear from you.

Already thx!