Costco paint is made by DuPont and is 100% acrylic. That already puts it in a top quality spot. Secondly it has a very high pigment count, so the white will be very white, even with a thin coat.
I had used the expensive Benjamin Moore white, but the costco paint was a lot whiter. Now the old Benjamin Moore looked gray compared.
Hiya Viking...
Take no offense, I really don't want to come across as petty...but I can never seem to help myself - so, apologies in advance. (BTW, this post is over 1 year old)
I've never tried Costco Paints and really know nothing about 'em so I am unable to give opinion to NW's question...But - if DuPont does make their paint, they do make some pretty good products (not sure about their architectural line, though)..
A little clarification on the other points...(1) 100% Acrylic really doesn't categorize a product as good or bad. It is true that acrylics are often regarded as premier resins (and they are), but it only tells a part of the story. As I've mentioned in other posts, there are over 100 different acrylic resins available to paint manufacturers today - and each has different performance characteristics and behaviors...some good, some not so good - depends on the design of the product - and, of course, each of these acrylic resins comes at a different price. Also, I can think of several examples where a modified acrylic will actually outperform a 100% solid acrylic - again, depending on what type of exposure the finish product is intended to be subjected to...and finally, if a product is 100% Acrylic resin - and is the finest, most expensive acrylic resin in the world - but is only 5% of the product's total composition, it really may not be that great of a product (but, at least it can be called !00% acrylic)...(which a product does not have to be 100% acrylic to be called 100% acrylic...strange, huh?)
(2) A "high pigment count" again won't really determine a product's quality without knowing the type of pigment (and the type of the type) - and what that "high count" actually means. TiO2 is the highest hiding, whitest, most commonly used "prime" pigment by paint manufacturers...but there are at least 4 types of TiO2 that have been used in paints - creatively named; Type 1, Type 2...and so on. Type 1 is hardly ever used anymore, but that's not to say it ain't either... relatively speaking, it's cheap. Type 2 & 3 are most commonly used in architectural paints, while Type 4 is used most often in automotive and extremely high end finishes. But TiO2 isn't the only pigment used - many other white pigments are used in both the cheapest and most expensive paints for a variety of reasons...these pigments are cheap, and white, and heavy, and provide some type of hiding (not necessarily the best kind), but the ratio is what's important in determining it's affect on the quality of a paint and, to some degree, the spread rate or mileage...and finally,
(3) I mentioned in an earlier post why some "white paints" appear gray and others appear whiter - sometimes, and not infrequently, high quality finish whites will appear gray - a design by the manufacturer to give better hide and light distribution while taking away some annoying reflective properties...
I'm really not trying to correct you - just trying to expound your reasons for calling a paint "good quality"...(plus sometimes I kinda just like to hear myself talk)...