Filter Formula Help: And, with OR and Not Equal To

Hi everyone,

I need help creating a Calculate measure that contains AND, OR, and NOT EQAL TO.

I've got a bunch of products that I am trying to group into 3 categories:  high quaility, b, and other.  And then find the volumes for each of these categories.

I was able to create measures to get the first 2 categories (high quality & b).  I need help with the other category.

Here is my attempt.

// Gets a specefic a product qty
High Quality A Product Qty = CALCULATE(
	SUM(FactCPRGradesheetDetail[InvoiceQuantity]),
	FILTER(DimProduct,
		DimProduct[MainProductName] = "A1"
		)
		)

// gets all of the b product qty
B Product Qty = CALCULATE(
	SUM(FactCPRGradesheetDetail[InvoiceQuantity]),
	FILTER(DimProduct,
		DimProduct[NationalProductRollup] = "B"
		)
		)

// NEW MEASURE ATTEMPT:
// Want it to grab the rest of the products not mentioned above
Other Products Qty = CALCULATE(
	SUM(FactCPRGradesheetDetail[InvoiceQuantity]),
	FILTER(DimProduct,
		DimProduct[NationalProductRollup] = "C" ||
		DimProduct[NationalProductRollup] = "Other" ||
		// NEED TO GROUP THESE TOGETHER SOMEHOW?
		DimProduct[NationalProductRollup] = "A" &&
		DimProduct[MainProductName] <> = "A1"
		)