Is this the same as Scope? Walgreens has the 1 litre on sale for $4.49 instead of $7.49. Then I have a BOGOF and a $1off which would make them a bottom line cost of only $1.75 each vs the $7.49 they usually are. The only problem is I'm not sure exactly what the Crest Pro-Health Rinse is. I'm thinking it's like Scope and if so I can use it. If it's something else, not sure that I need it even at such a good deal. Somebody clue me in!