Then I wouldn't go quite that high. 150% weight in protein is more conducive for muscle building. You can get away with significantly less while losing weight. The best way to figure it out might be to figure out about how many calories you need to eat daily for steady weight loss (identify your BMR as a starting point). Then take 25 to 30% of those calories for protein, 40 to 50% for carbohydrates and 20 to 25% for unsaturated fats. It's an easier way to get a good balance of nutrients as you lose weight, but still get enough to maintain you current lean muscle to keep metabolism high.
As far as high protein foods, lean meats like chicken and turkey breast, fish (even fatty fish is healthy), eggs, soy, beans/legumes, dairy (milk, cottage cheese, natural youguts), occasionally very lean beef, and if you want to get a little saucy, game meat like venison and elk is very high protein. A super quick protein fix is a can of tuna. 37g of protein, 1g fat, 0g carbohudrates, 150 calories and 50 cents. Can't beat that.

If you still want to use whey powders, Designer is okay, but you get more for your money going for the 5 lb tubs like Optimum Nutrition. Check online shops like DPSnutrition and Netrition for good prices. It pretty much comes down to taste. Maybe try a smaller can of something to see if you like it before getting a larger one.