I use Isopure's strawberry powder simply because my cost is under 9 dollars a pound. You can get it for the same price from the protein factory, but I'm not crazy about their flavors. With Isopure, I love the taste, mixes easily, and I get zero gas or bloating. The bottled Isopure tastes even better BTW.
For a better description of the Ion Exchange process, here's an excerpt from the protein factory:
Scientific Description
Manufactured from fresh, sweet dairy whey. Using the ion-exchange process the proteins are separated on the basis of their electrical charge. The extraction works by controlling the electrical charge on the proteins using chemical reagents. The electrical charge on the proteins attaches them to resins in the reaction vessel. The product contains the proteins beta-lactoglobumin and alpha-lactalbumin. It is instantized and mixes very easily with a spoon. It is also fat and lactose free.
Bodybuilding and Athletic Supplementation Description
Ion-exchange whey isolate is excellent for any athlete wishing to try an alternative to whey concentrate. If one experiences bloating and other digestive problems, then IEWPI is a good choice. This protein mixes very easily with a spoon and probably is the best tasting protein in the Protein Factory's selection. One advantage Ion-exchange whey isolate has over CFM is that it has a 5% greater protein percentage. Which means your getting more protein for your money.