Not sure whether I want to watch 'Them'

I seem to be reading conflicting reviews. Most people are saying that 'Them' is just 'Him' + 'Her' with some scenes taken out. Others are saying that it in fact adds a few new scenes and is a part of a legit trilogy. Well, so which is it?  Did people's appreciation for the movies increase after watching the final instalment, or would they have been okay without watching 'Them'?

Also, does anyone else share my overwhelming need to know exactly *which* version of each of the shared scenes was more true, given the pretty big disparities in dialogues and expressions, and do they feel that 'Them' did a better job of answering these questions?