Get Perfection With Domain Change

Change as per your requirement :)
But tell Google about your domain change
Normally, when website owners change their domain names as per their company's ongoing requirements, most of the webmasters and website owners face a headache to get along with the new domain name and its age in terms of Google Page Rank. Now it is a good news for everyone who are interested in changing their domain name.

Google has announced a new feature in Google Webmaster Tools named change of address. This feature allows webmasters to notify Google when they move domain names.
Further more, Google also states that one should make sure that their original site is not a subdomain (for example, http://newsite.example.com).

Finally, Google posted a help document on moving your domain to aid webmasters with this process.