If you want casual comfort along with waist training, then cotton corsets are the ideal choice for you. It may take some more time for seasoning, but once you are comfortable with it, you will feel as easy as your denim jeans.
This is both available as overbust and underbust. For the overbust corset, it will cover your bust area along with the waist area and this is ideal to wear under any dress. Underbust corset provides full coverage for the waist area and this is ideal for waist training. In that case, stealthing in cotton corset is little thicker because it uses thicker fabric with more texture.