First, drop any hope to find it by the name (just look for the "vegetarian food" sign -- I wasn't sure I was there until I saw the photos here on the site).
Second, I can't say I enjoyed just any single part of it. I'd ate a noodle soup and some rice with various veggies and sausages they had to offer, and drunk some ice tea, and all of it was a complete disaster to all my senses. Sausages and some stuff in the soup seemed (and tasted) so close to a real meat so it made me wondering if it really was a vegan place at all, desptite all the "vegetarian" signs. It tasted awful, ice tea was some mix with orange and whatnot and I'd preferred soda water if I knew how disgusting it was. I haven't discovered anything like eggs or dairy, hence if it's indeed vegetarian it's most probably vegan.
Those Thai spices and whatever they put in the food smelled like stuff in fish markets, so disgusting. Maybe ones who love Thai/Asian stuff might like it, but definitely not me.
It's an open street cafe, like most of cheaper local places, so be prepared to heat and street noises. But you probably already know that if you ever were anywhere in Asia before. Any closed place with an aircon would be more costly.
Conclusion. It might be vegan, but I don't want to ever try it again anyway. I'm staying in Pattaya for the whole winter and strongly prefer supermarket frozen foods and Indian places ever since (there are a lot of lacto-ovo-semi-vegetarian, usually vegan-friendly Indian places and they usually aren't disgusting. Besides, Indian folks usually know English better so explaining that you want some vegan food is usually easier there than in almost any Thai place).
Try it if you're vegan/vege- and wanna know what real Thai food looks and tastes like. You might not like it, you might vomit a little, you might want to get home ASAP and eat a dozen of vegan pizzas and burgers in order to forget that place, but you would at least know for yourself, and experience is all that matters if you're exploring SE Asia :)
Updated from previous review on Monday September 22, 2014
Cons: Open (heat and street noise), Everything smeels and tastes disgusting, Awful place by overall experience