If I were you: I'll be definitely looking into Ricoh 9110. Request a demo with you're stock and you're application.
I run an Indigo 7800 and I was a litho minder until 6 years ago. We have litho too and quite often run make-ups on the indigo of jobs that come up short. I have not seen another digital press that can match litho so closely. I believe you need to be printing around 2 million clicks per month for it to be worthwhile.