I've tried a number of vegan protein shakes: hemp, soy, pea (tried 3 different pea ones!) and have only found one that I really like.
Its a 100% pure pea protein isolate called Vegan 90. For something that has no chemicals, no aspartame or other sweeteners, no whey or other dairy products, this stuff is incredible, and it tastes great too.
I can't recommend it highly enough. However I'm not sure its available outside the UK. And other 100% pea protein shakes I've tried have been awful, so there's no guarantee a pea protein shake will be any good.