I hadn't bothered because of the aforementioned reviews, but if your experience is the norm, I might have to reconsider!
I wrote a somewhat in-depth review on Best Buy.com for the six-pack if you're interested. As of this moment, I've rewatched I, II, IV and VI. I think this transfer breathes quite a bit of new life into the movies. Watching TWOK was just damned cool to an already damned cool movie, and I have to say that they chose the right movie to completely restore. I think they're pretty thoroughly enjoyable.
This is because the general internet population is made up of horrible stupids; reviewing down products on Amazon and similar sites based on something you overheard is the hip new thing for people who are dumber than dirt.
The actual story is that only one of the films had a new, restorative transfer (Wrath of Khan). The others used existing transfers done some years ago. This is *NOT THE SAME THING* as being "upconverted" from a DVD -- it means they're taken from the same *source* as the DVD, which is of a much higher quality than a DVD or a BluRay. This is all very interesting to film historians, AV geeks and people with giant TVs who will notice various tiny problems with the older transfer... but it doesn't impact the average viewer one bit. The problem is that reviews written for those groups of people make it out to complete idiots and... here we are. (Note, even, that the vast majority of catalog BluRays don't get restorative transfers -- Wrath of Kahn is a cool exception, not a rule that's being violated by the other five movies. Studios use their existing scans for almost everything).
(The other 'problem' is that these are all the theatrical cuts of the movies instead of the various special editions. I personally think it's great to *finally* have these versions (this version of ST6 wasn't even on VHS)... but other people are somewhat-more-understandably pre-angry at the fact that they'll sell us the extended versions of several of the movies in a few years.)
And I think you've summed the entire thing up...couple that with the fact that someone on Amazon titled their review something like, "I actually WATCHED what I review!", your explanation makes a perfect-sense tie-in.
The one thing that annoyed me on even the most recent DVD Director's Cut release of TWOK was that those damned rips in the film were still there, as those little black holes pop up from time to time in places. I loved seeing the film fully restored. All of them look great, but TWOK was evident in having the most work done on it.
I thought that Star Trek: The Motion Picture looked nothing short of fantastic. I was just severely disappointed that it wasn't the director's cut (as I was for all of the movies).
Just me, but I actually prefer the BD copy they used...it's not the jazzed-up version they released a few years back, but it's not the cut-up theatrical version either...it's somewhere in the middle. The director's cut of TMP annoyed me in that they even cut *lines* out that didn't make sense to do. For example, Chekov's report of "Force fields and deflectors up full, Keptin!" during V'Ger's first shot...the most recent DVD director's cut took a scissor job to THAT line, snipping up the extra two seconds to say, "...full, Keptin!" For someone who's not seen it, it's no big deal, but knowing it's there...well, let's just say that I hate 99.9% of film editors.