Typically if the same model is available, than that's what you get. My wife had a Blackberry 8330 replaced with another 8330 1yr11mo after she originally got it. Less than a month after getting the new phone, she upgraded to another one with her 2yr renewal. If they have a refurb Dinc to send, than that's what you'll get. Next week someone else may get a D2, and the week after your old-now-refurb may go to someone else.
Some stores even have somewhat of a service center, a speaker replacement is pretty simple, and you may not need a new phone at all in that case.