I always use Compete intraworkout.
but you have to make sure that you give your body time to digest your previous meal... i eat 2 HOURS before my workout, then I have my intra shake while training
people will eat 30 mins before the gym, then start chugging an intra drink loaded with carbs or aminos.... that chit isnt getting digested till you are probably done...
if you are having a "pre" shake, i would skip the intra, unless its a very long workout that will be ~2 hours like a ridiculous leg session or something