I'm not sure of the context of the question. If your new owners are going to consolidate they are basically going to do it one of two ways:
1. Create all new users, computers, resources, etc in their domain for your company, then change everything over and shut down the old domain.
2. Do a migration where AD objects are migrated into their domain, maintaining SID history, and then migrate the resources from your domain into their domain.
If they go with option 1 it will be painful. If they go with option 2 it will be slightly less painful, but they will need a migration tool like ADMT or one of the Quest tools to do this.
Is your question whether using ADMT is better than the alternatives? ADMT is free so that's a big win for it, but whether it is the best choice will depend upon what your environment looks like, how big your AD structure is, how complex it is, whether it was built to "best practices" or just grew willy-nilly, etc.
________________________________________
CompTIA A+, Network+, Server+, Security+
MCTS:Windows 7
MCSE:Security 2003
MCITP:Server Administrator
MCITP:Enterprise Administrator
MCITP:Virtualization Administrator 2008 R2
Certified Quest vWorkspace Administrator