I've been using Cytogainer for a while now and have tried 4 flavors. Ranked, out of 4 stars:
Chocolate Mint:
While I'm not crazy about mint in food (prefer it in gums and...well...mints) this really is pretty amazing for a weightgainer. Smells and tastes like liquid Girl Scout 'Thin Mints', or Junior Mints.
**** 4 stars (for a weightgainer/protein, easily)
Chocolate:
Pretty good, standard chocolate fare. Probably would be much better with milk (I always mix with water.) Sweeter and tastier on it's own than say ON 100% Whey's chocolate, which is more like cocoa.
*** 3 stars
Strawberries 'n Creme:
Just got a tub of this today, drinking it now... not so great. Generic sweet taste with weird artificial strawberry flavor. Might as well be called "Pink" rather than strawberry. Very weird aftertaste with a sour tang.
** 2 stars
Cookies 'n Cream:
Has a very strong "protein" taste to it, like the first cheap proteins I used to buy...a sort of putty like smell/taste. Taste isn't horrible, but still pretty shitty overall. Chuggable, not recommended at all though. Probably wouldn't even taste better with milk.
** 2 stars
I'd stay away from CNC and strawberry, but I still gave them 2 stars as I haven't had any problems downing them, they're far from repulsive.