Difference between Isolate and Protein powder?

Can anyone explain what the difference is between whey Protein powder, and Isolate Protein Powder? I can see by the label that the Isolate has a lot more protein, less carbs, and more calories than the regular protein powder, but is it worth the difference in price.

The links below are for a protein company that I have use in the past... about 10 years ago when I was really into working out the people who really knew their stuff recommended and used the econowhey by sci-fit, I used it, it taste great, and was fairly cheap back then. Fast forward ten years I google sci-fit and see the company has gotten much bigger and now has a lot more choices. I am tempted to order the Whey isolate even though it has twice the calories, I will use it as a Meal Replacement (breakfast) and to make sure I get all my protein in for the day. know this company does not make false accusations about the stuff in their products because years ago they used to have a deal that if bought the product and took it to be analyzed, and it came back with less protein or more carbs they would write you a check for 1500.00. Long story short I know they make good tasting stuff, and they are a stand up company, bummer is it has to ordered over the internet because I cant get it locally.

Sorry to ramble on so much, back to the original questions.

Other than the obvious stuff we can see on the label is there a difference I should know about when buying the Isolate rather than the faithful old EconoWhey?

Is Isolate good for bariactric use?

Has anyone used Isolate?

Here are the links

Econo Whey PDF of Econo whey label

Isolate Whey PDF of Isolate Whey

Any info would be great.