(a) the agreement may provide for remedies in addition to or in substitution for those provided in this article and may limit or alter the measure of damages recoverable under this article, as by limiting the buyer's remedies to return of the goods and repayment of the price or to repair and replacement of nonconforming goods or parts; and
(b) resort to a remedy as provided is optional unless the remedy is expressly agreed to be exclusive, in which case it is the sole remedy.
(2) Where circumstances cause an exclusive or limited remedy to fail of its essential purpose, remedy may be had as provided in this article.
(3) Consequential damages may be limited or excluded unless the limitation or exclusion is unconscionable. Limitation of consequential damages for injury to the person in the case of consumer goods is prima facie unconscionable but limitation of damages where the loss is commercial is not.