You should probably be aware that neither Sherwin Williams nor Dunn Edwards make any of the stuff they mix together to make their house paints. In fact, as of about 10 years ago, Sherwin Williams was using an acrylic binder resin made by the Rohm & Haas company called Rhoplex HG-95P to make their gloss and semi-gloss SuperPaint. Rohm & Haas was bought out by Dow Chemical in 2009, and Dow now markets that product under the same name:

http://msdssearch.dow.com/PublishedL...romPage=GetDoc

The point here is that Dow will sell HG-95P to ANY paint manufacturer, just as other chemical companies will sell their pigments, coalescing solvents, rheology modifiers, defoamers, etc. to anyone wanting to make paint commercially, and if that manufacturer is competent enough to mix the chemicals in the recommended proportions, that manufacturer will make a paint just as good as SuperPaint.

And, the sales reps from every one of those chemical companies are continuously taking the managers at the paint manufacturing companies out to lunch to tell them about their latest and greatest offerings in the hopes they'll buy that resin, pigment or chemical. So, making the best paint in the world is not an engineering challenge; it's a management decision. Management has to decide whether or not the benefits provided by using a newer binder resin or pigment or chemical warrant the increased cost, and if so, they'll buy it to use in their paints. If not, they won't. It's as simple as that.

So, that's why it's often said that when it comes to paint, you get what you pay for. But, it's equally true that when it comes to paint, you often don't need everything you get. In my case, I own a small apartment block, and when I repaint apartments, I'm repainting them the same colour. So, does it make sense for me to pay extra for a paint with good hide? Not really.

So, instead of going according to whose name is on the can, you'd do well to just phone up the managers at any of the major painting contractors in your area and ask them what paints they've found work particularily well over bare stucco in your area. Most likely you'll find that there's no concensus of opinion as every manufacturer's top-of-the-line exterior latex works well, and the differences the paint company managers will spend most of their time talking about are if you're gonna use a sealer first, the weather conditions before, while and immediately after painting, the method of paint application (roller, spray, whatever), whether you're gonna put on a second coat or not and stuff like that.

All paint companies make the best paint they can put together for what they consider to be a reasonable price to pay for good paint. The difference is that they all have different amounts in mind when it comes to what good paint should cost. If you pay more for your paint, you generally get better paint, so the trick is to buy the most expensive paint from the place that sells it the cheapest. But, it's really whether you use a sealer to prevent the stucco from absorbing paint, that you're painting under proper weather conditions, and whether you put on only one coat or several that play the biggest roles in whether you run into any problems painting, and how long your paint job lasts.

I know that's not the simple one word answer you were looking for, but it's the correct answer to your question.

PS: This business about latex paints not being able to expand and contract with stucco, and the result being that the paint cracks and peels is a perfect example of why you can't believe everything you read on the internet. Wood is a natural material that expands and contracts with changes in it's moisture content usually caused by seasonal changes in temperature and humidity. The primary reason for oil based paints to come in both interior and exterior versions is that exterior versions will be made with more oil and less alkyd resin (called "long oil" paints) so they don't dry to as hard and brittle a film. That's done precisely so that the oil based paint retains enough elasticity to stretch and shrink with wood outdoors. Both interior and exterior latex paints have more than sufficient elasticity to stretch and shrink with wood outdoors, so the biggest difference between interior and exterior latex paints is the amount of additives (mildewcides and UV blockers, really) there is in each can. Wood can shrink by as much as 8 percent from "green" (recently cut) wood to oven dried, and that's vastly more dimensional change than you're ever going to see in stucco, especially due to thermal expansion and contraction. Exterior latex paints work fine on stucco; you don't need an elastomeric coating to paint stucco.