It's that 48 chromosome type that I think makes it interesting. As a rule, TBs and other 48 chromosome iris are derived from an incredible diverse gene pool. Anytime you could work with a plant where half the chromosomes are from a species or produce plants with half the chromosomes from a species, you have just taken a bite out of all the diverse unknowns you normally work with. It might tell you a good bit about the plants you use with it in a way that others crosses can't reveal. The contribution from junonia should be entirely more predictable in what it brings to the table and, in fact, mostly predictable and identifiable after a bit of use and observation. That could make use of the plant mates more effective, because you'd be better able to identify the specific traits they are laying out with the junonia genes. My cattle background is probably showing here, but if you're working with uniform genetic groups, you can get somewhere a lot faster than if they're more mixed up. Iris are still more complicated, but in the initial cross with junonia you've still cut it in half once you know how junonia works. Ib-Mac always appealed to me for that reason, but I lost it and haven't been able to replace it yet.