I reply: ********...
Few will be better than the parents. Some will be as good as the parent. The vast majority will see the twisted dorsal of Rex reappearing with the narrow dorsal of Val, or the crappy color of Rex on a Val shaped flower...
I never believed in the F2 generation sanderianum hybrids as being 'overall excellent', because the F1 had at least one parent with short petals... A few plants will be amazing, but the vast majority will get the narrow dorsal of sanderianum and the short petals of the other parent...
The only way to work this around, and that's a long one, would be to sib Prince Edward of York, bloom the seedlings, and select the ones with long petals and wide dorsal... Or for Michael Koopowitz, go one step further, cross it back to sanderianum, bloom them, and sib them, to get in the next generation really long petalled, nice dorsalled plants. This is not commercially viable.