This is a really tasty vegetarian restaurant offering a very large range of Vietnamese dishes. The whole menu is allergy marked and I'd guess about 50% are listed as gluten free. We chose a handful of different things and enjoyed all. There was one minor issue where they brought us soy sauce with our dish and we asked if it was GF before we tried it and it turned out it wasn't. This made us a little more dubious about certain things but neither myself or my celiac partner had any issues and I'm sure we'll go back again.
*EDIT - MENU WARNING*
Just to add that sadly I've gone back to shamballa a couple of times with a celiac card and every time I've gone and chosen a different GF Dish each time there have actually been gluten ingredients that they've had to warn me about or switch out. While I appreciate them being honest with me, it means that their entire menu is basically incorrectly marked.
— Not very
— Gluten-free items are marked on the main menu
— Not Much
— Excellent