Hydrophobic is a relative term.
Actually all the BCAA's will dissolve in water to a reasonable extent: valine to 30 g per 16 ounces, isoleucine to 14 g per 16 oz, and leucine to nearly 10 g per 16 oz (NOTE: leucine value is edited from previously wrong figure: I had accidentally given the dl figure.)
The problem is not so much solubility, unless attempting to use less water than this, as it is rate of dissolution.
Rate is improved with smaller particle size and witm mixing. Biotest Leucine powder dissolves faster than some others due to the particles being very fine. It is not the case that BCAA's will never mix with water, only that it is a rate-limited process, with rate much more severely limited with large particle size.
On the taste: while personal experience may vary, my experience was the palate slowly adapting to the taste. Rather as a person may think buttermilk (for example) tastes awful at first but later finds it acceptable, the same sort of thing happens here.
BCAA's can still for me turn something fairly tasty into something just entirely acceptable, but aren't nasty-seeming anymore. This did take a while though.