We did look at the 23ikss and it is beautiful............ however, after weighing the pros and cons, my DW and I came to the conclusion that since 95% of our cooking is done outside, we didn't need that kitchen with the island. The rear private bedroom was more important to us.
I don't think the open floor plan is much bigger in the 23ikss, since the island is in the middle of that floor.
The Roo 23ws and 23ikss are two beautiful hybrids
and like all campers, it comes down to what suits you the best .