What brand was it that allowed you to cut into your countertop?
Had never heard of Alvin cutting mats, so looked them up on Amazon. (Amazon is a great place for getting user reviews of different products.) They get good reviews. Olfa seems to be the most popular mat among quilters; not sure how Alvin would compare to Olfa. It seems comparable.
Be sure to do a lot of price-checking before ordering. Sometimes Amazon and other places regularly offer a product for less than websites that advertise the same thing at 50% off. Also be sure to check size of the mat as it relates to price.