Will This Domain Change Hurt

[DeliaAssociates]

I have a potential client that is looking to change their domain for branding reasons, but does not want to lose their solid SERP position.  I'm not concerned about links continuing to pass juice as he was (though I am concerned about the link profile).

What I am concerned about is domain age (moving from a 4 year old domain to one that has just been parked for 4 years but not used, or one that is currently just a redirect to his site), and the fact that his current URL is an EMD.  He is using his state (only really does work there), plus two solid keywords in the domain, and wants to switch to brand name with one of the two solid keywords he was using.

My initial thought is "if it's not broke, don't fix it."   How worried should I be about rankings if we change this domain.

Thanks for the help, and fire back any questions.  Sorry I'm a little vague.

[irvingw]

you should never change your domain name unless you absolutely have to, once you choose a domain name you should consider yourself married to it since it could affect rankings.

What kind of traffic are we talking about, and how much does his business survival depend on his site ranking, these factors would make a difference in deciding if the risk is worth it.

if it's for branding only he could redirect a branded domain name to that url and have it show as an alias. and also be able to use the branded domain name in business cards etc but the site will still be indexed under the original domain name.