I'm using this stuff at the moment(mint choc) and i don't find it any thinner than maximuscle promax i've used in the past.

I use it in a shaker with 1 scoop (35g i think) with 250-300ml of water and 2 ice cubes and just wolf it down.

I have also used USN Weight gainer which was like a stupidly thick yougat to drink! Not nice at all