I did 4 nights at Dari and 6 at Kila earlier this year.
First, I completely agree with other posters to skip Ubud altogether and just go to Kila. I found Ubud to be closer to a tacky tourist spot than to a cultural experience. Whilst I found Kila to be my best resort stay ever. Cannot say enough positive things about Ernst & Shane.
That said, if you do decide on Bali I'm going to part from the crowd a bit here and suggest you consider Mandapa. I enjoyed Dari, but compared to my previous Aman stays there just wasn't a wow factor. The villas are large enough and to me didn't see dated at all. And I think they aged well. Everything seemed polished, but it just didn't have the same feeling for me. Can't really pinpoint it. It could be because I found Ubud so unappealing that after 1 day out just stayed at the resort. And Dari is so small that it felt a bit claustrophobic after more than a day or two.
I hate to admit it but I remember looking down at Mandapa from the pool area at Dari and wishing I was there instead.
But again, why bother with Ubud when you can just do Kila the entire time?