I love Vega! I haven’t tried the different flavors, though, because I like being able to TASTE the fruits and veggies in my smoothies. With any nutritional and diet/food regimen, you have to find what works for you. Since you’ve only tried it once, it’s hard to determine what caused your stomach pain. What have you tried? You might have had some kind of food intolerance. There are lots of nutritional shakes out there…whey, casein, soy, plant, etc. It’s really a trial-and-error thing. I also think it’s a good idea to gradually add these nutritional shakes into the diet; meaning to say, don’t use the full scoop the first few times or so. Sometimes, taking the full “dosage” right away can be upsetting to our body. It’s the same with medications a lot of the time. It’s also not unusual for the body to go into a “cleansing” process with these shakes. It’s like acne medication- it gets worse before it gets better…that’s because the body is flushing out the toxins and all these no-good-stuff need to exit the body in some way. I say, if you really want to incorporate a nutritional powder/shake into your diet, try a few more and just see how your body reacts to them. There should be one-serving packets out there, so you don’t have to buy an entire container. I do recommend plant-based nutritional powders, though :) Good luck and I hope you find one that will work with your body.