I found that the Muscle Milk Cake Batter Protein tasted great in cold water.

personally i can only drink whey isolate in water. and it has to be fruity flavored. isopure is one of the ones that tastes great in water.

almost any of the ON flavors work well. um, dymatize elite is good in water, most are not bad
i personally prefer using milk, but water is now my choice due to convenience around time and location of my workouts

Scivation Chocolate is great in water, and the Dymatize 12-hours are great too. ON Chocolate Mint is better with milk but tasty in water.

I've found "The Isolate" by 4EverFit to be the best in water, by far. Other fruit flavored isolates such as those by Ergopharm and Nectar by Syntrax would likely taste quite good as well.

Dymatize Chocolate Mint is quite a hit in water too. The mint goes a long way with that particular flavor.

Its weird but prefer water instead of milk with Ultra Peptide 2.0, any flavor. Muscle Milk as well maintain the taste, the problem is mainly with pure whey or whey blends.

I've tried almost all flavors of ON and i gotta say that Rocky Road, Caramel Toffee, Chocolate Mint taste pretty well, but imo Met-rx Ultramyosyn PB cup taste awesome in comparison.

Most of isolates comes with fruity flavors that can be mixed with water rather than milk for a better taste.