I would rather go after Monroe.
Why Monroe over Ibaka? Post scoring?
Seems like a more willing trade partner (Milwaukee). Orlando looks bad if they just dump him after what they gave up for him.
We probably get Monroe for this season plus 1 more.
Monroe would be looking to prove some people wrong (Ibaka is kind of just playing to FA).
I think Monroe is overall a better player based on the historical performance that I have observed.
I think Monroe in a situation where he does not need to be "the guy" and is motivated would give us more of what we need than Ibaka.
We could do something really crazy and try to get them both. We have Amir and Zeller adding up to $20M in trade ballast. Throw in Jerebko and it is $25M. That and a couple of not so important future picks or current stashes probably could get us both (assuming Orlando is looking to move Ibaka like Milwaukee is reported to want to move Monroe).