I fed my baby with Healthy Times Brown Rice from six months, and he has no problem. He has now tried oat and barley cereal from them as well.
Their texture is quite soft, and there certainly wasn't any problem with my baby eating it. I think it is mentioned on the box that it is ok for 6 months old babies. They recommend starting with the brown rice, then progress to oat, barley, and multi-grain.
Now, my baby eats Ballamy's rice cereal in the evening, and Healthy Times barley cereal in the morning. He likes them both very much. These brands are both organic, and not so sweet.