I find it starts getting good enough to use after six weeks. Especially if there is 2% salt in the recipe. The salt just helps them stay stiff as they are used up.
My salt free bars are six months old, and they are reasonably hard until they are about half used up. At that point I just fold them in half so that they aren't so floppy.
With RBO, I've never seen the "snotty" effect Ive seen discussed with 100% OO soaps. But they do lather differently than a soap with coconut oil in them. RBO soaps feel kind of sticky as I rub the bar on the loofah. The soap cream that rubs off remains a little sticky until you give it a little more water. Then it explodes into creamy, silky lather. Its like the soap is thirsty and just waiting for that extra bit of water to really show you what it can do. I love them for shower soaps.
CO soaps are lathery right off the bar, but don't have the same creaminess.