In other words. If YOU examined the product the implied waranty no longer
exists.

see § 25-2-316 3. (b)

From: http://www.ncleg.net/homePage.pl

§ 25-2-315. Implied warranty: Fitness for particular purpose.
Where the seller at the time of contracting has reason to know any
particular purpose for which the goods are required and that the buyer is
relying on the seller's skill or judgment to select or furnish suitable
goods, there is unless excluded or modified under the next section [G.S.
25-2-316] an implied warranty that the goods shall be fit for such purpose.
(1965, c. 700, s. 1.)

§ 25-2-316. Exclusion or modification of warranties.
(1) Words or conduct relevant to the creation of an express warranty and
words or conduct tending to negate or limit warranty shall be construed
wherever reasonable as consistent with each other; but subject to the
provisions of this article on parol or extrinsic evidence (G.S. 25-2-202)
negation or limitation is inoperative to the extent that such construction
is unreasonable.
(2) Subject to subsection (3), to exclude or modify the implied warranty
of merchantability or any part of it the language must mention
merchantability and in case of a writing must be conspicuous, and to exclude
or modify any implied warranty of fitness the exclusion must be by a writing
and conspicuous. Language to exclude all implied warranties of fitness is
sufficient if it states, for example, that "There are no warranties which
extend beyond the description on the face hereof."
(3) Notwithstanding subsection (2)
(a) unless the circumstances indicate otherwise, all implied warranties are
excluded by expressions like "as is," "with all faults" or other language
which in common understanding calls the buyer's attention to the exclusion
of warranties and makes plain that there is no implied warranty; and
(b) when the buyer before entering into the contract has examined the goods
or the sample or model as fully as he desired or has refused to examine the
goods there is no implied warranty with regard to defects which an
examination ought in the circumstances to have revealed to him; and
(c) an implied warranty can also be excluded or modified by course of
dealing or course of performance or usage of trade.
(4) Remedies for breach of warranty can be limited in accordance with the
provisions of this article on liquidation or limitation of damages and on
contractual modification of remedy (G.S. 25-2-718 and 25-2-719). (1965, c.
700, s. 1.)