1. Usually, the cost of domain name transfer is higher, and it takes longer, the specific time varies from platform to platform. External domain push takes less time and generally can be completed on the same day it's initiated.
2. Transferred-in domain's registrar interface will be changed, while the external domain push will not. For example, if a domain name is external pushed from InternetX, then the domain's registrar is still InternetX.
3. Despite the price advantage, but there are certain restrictions. External domain push is not supported by all platforms, and not all extensions are supported.