iRule Rewrite in Browser

Thanks  .

I'm trying to avoid putting a redirect on a VS that could live forever so my thought was to point the IP for www.testsite.com to the same IP as www.newtestsite.com and have an iRule basically change the Host in the browser so the client wouldn't know the difference. Something like this?

 when HTTP_REQUEST {
	
	if { [HTTP::host] equals "www.testsite.com" } {
		
		[HTTP::header] replace Host "www.newtestsite.com"
		
	}
	
}

Would that show as updated in the URL that the client would see? I've never replaced the host header and we typically do redirects so this is something new.