[Unanswered]  Question about Xtend+

My runtimes of pP00CXt+ has decreased by a 4-5 seconds. Some say that my Xtend+ is wearing out, is it true? If it is, then which part of Xtend+ wears out the chip or the Xtend? A seller is selling me a Xtend which he has never used but it is not a box/packet. Will it be as good as a completely “fresh” Xtend or not? 
Sorry if you think I am going in too much depth, I am just obsessed with stamina drivers.
THANK YOU for your answer. Means a lot.
Well first off the add on can never really wear down. It’s probably the main part of the driver, so you may need to get a new Xtend and put the add on on it.