I have been to Banana Leaf a number of times. It's exactly as advertised.
They have a menu, but I've always done the chaat + buffet option. I'd recommend doing this, at least the first time you go. You'll get full, but it's tasty and you get a range of things.
My only complaint is the buffet. Sometimes they have great things, sometimes the choices leave something to be desired. I'll go one night and love everything; I'll come back a few weeks later and there won't be anything that stands out. Don't get me wrong, it's never anywhere near *bad*. There are a few things that they do really well. The eggplant and okra dishes in particular stand out; it's a shame they aren't there all the time.Pros: Good food., The chaat + buffet will fill you up.
Cons: Price slowly increasing., Inconsistent choices.