Keep in mind in the US they are showing the 2.39:1 AR Scope version. In 2012 when they did the remaster, they supposedly showed the better 1.78:1 version so thats a bummer seeing the original 2.39:1 version and not the version that Cameron (I think) prefers.
However, this time around you get HDR and HFR (in addition to the 4K and 3D you got in 2012) so thats nice. On the downside, when I went to see it, the HFR scenes were very limited and oddly chosen seconds here and there so i'm not sure if it adds anything. Frankly I feel the same about the 3D. While this film is a pretty good implementation of the technology, was anyone really asking to add 3D to this movie?
I missed the 2012 remaster for the 100th anniversary of the sinking. I feel fortunate to see it in theaters this time for the film's 25th anniversary.
For the record I have seen in AMC's Dolby 3D and Cinemark's XD implementations. I think they both use dual laser projection. I have skipped the standard 2K version.