However for me I am just glad I have the directors cut!
As I type this I'm watching it playing on my new upconverting DVD player into my new 26" 720p LCD TV. It looks so beautiful I could cry. I can SO wait for an HD version. In the mean time, I can see the makeup where Spock's ears were applied. Too much definition can be a bad thing as well.

OK - I'll repost this link with comparison screenshots.
http://www.dvdtimes.co.uk/content/id/70794/star-trek-the-motion-picture.html#thumb
Scroll down to the comparison of the Starfleet HQ pics. And then tell me which version compels you to cry.
After seeing Star Trek XI on the big screen I decided to enlarge my small Star Trek dvd collection. (only had the 2-disc set of TWOK). I picked up the new 3-disc "trilogy" (ST 2,3 &4) and then borrowed the 2-disc sets of ST:TMP, ST5 and ST6 from the local library in order to decide if they were worth buying. (I had only seen TMP once on television way back in the eighties, and have never seen ST 5 or 6 before.)
Anyway a couple of days later I did also buy the new dvd's of TMP, ST 5 & ST 6. And I can tell you they all look better than the old dvd's. (and at the bargain prices these dvd's are selling for they're a steal. 18,90 EUR for the 3-disc set and 6,90 EUR each for the TMP and ST5 & 6 dvd's)
Also Star Trek 6 is presented on the new dvd for the first time in it's original aspect ratio of 2,35 :1 instead of the 2,00 :1 ratio of the old dvd. Which improves the composition of the movie.
comparison screenshots =>
http://www.dvdtimes.co.uk/content/id/70821/star-trek-vi-the-undiscovered-country.html
Now the three weeks in which I could compare both versions of TMP left me underwhelmed by the merits of the DC.
In my opinion only two shots are better in the DC.
1) the explosion at the end of the wormhole sequence.
2) the alien probe disappearing when Spock transmits the code as seen from outside the Enterprise.
And these shots combined last about 10 seconds tops...
The DC starts out with 3 ruined scenes.
1) Overture with superimposed windows screensaver starfield giving us the impression of flying backwards through space.
2) Main titles with gaudy golden typeface.
3) the DC managed to trim the Klingon battle sequence. The most exciting scene of the movie and it gets trimmed...
Then some random scenes are added that don't particularly help the film.
1) Uhura dissing Deckard and praising Kirk. I mean is she a professional or a Kirk-groupie? After all it is Deckard who saves the ship twice. In the worm-hole and at the end by merging with V'Ger.
(this scene and for instance the added scene just before McCoy transports aboard also cause the launch of the Enterprise to take place later in the movie making a slow-paced movie even more slow-paced.)
2) Ilia healing Chekov.
Also in the Director's cut the V'Ger ship is shown in it's entirety. It seems slightly larger than a Super-Stardestroyer out of Star Wars. (Vader's command ship in "Empire") In the theatrical cut the V'Ger always seems immense.
The DC-effects of the V'Ger-bridge scene already look dated. The old scene had a less than perfect matte painting of the Enterprise but at least it was part of the original movie.
Both cuts are new to me so maybe that explains my point of view. Someone who has lived with the DC for a number of years and is really convinced that it is better than the theatrical cut may find it harder to like the new dvd-version.
Ideally all versions should be released in excellent quality (like Spielberg did with his ultimate Edition of "Close Encounters" or the Blade Runner 5-disc set.)