I wouldn't go. My kids are 4 and 1 and we've never been there. I've read several dining reviews that it's a very small, very intimate space NOT kid friendly. However, if you had a well mannered 6 year old, I'd go. Just not 3 under 3.
Do they even have room for two highchairs at the table???
Eat in Mexico, the kids will enjoy it much more! Or Japan! My DS4 loves the table action at Teppan Edo.