I enjoyed the original BGC when I first saw it, which would have been around 1995 and the start of my anime-watching career. I've watched every episode several times. I like it, but I don't consider it to be the crowning achievement of anime, as some do. I've been buying and watching the BGC: 2040 DVD's as they've been released. I think I like it about as much as the original, but for different reasons, because it has different strengths and different weaknesses.
No plot spoilers.
The story opens with a focus on Linna, which is welcome, as she was the KS most cursed with inadequate character development in the original OAV's. We meet her when she comes to Tokyo as a young career woman (she's not an aerobics instructor in 2040), watch her first learn about and then join the Knight Sabers, follow her struggles in learning to fight boomers, her conflicts with the other KS's, and her stresses in trying to fit her avocation as a KS into her life as a normal young Tokyo woman. We see the KS's through her eyes, which is interesting. Meanwhile, a back story involving Genom, the boomers, and the Stingray family has been slowly building, and takes over the focus of the show at about the middle. At this point, too, the character focus moves away from Linna more onto Nene. Sylia gets some attention, though not enough in my book, and Priss gets scandalously little attention through the entire series. Daily is no longer gay, or at least there's nothing in his dialog or actions to suggest it. Leon gets a fair amount of face time with the viewer, although we don't see much character development. Mackie is little more than a plot device.
I really don't like the new character designs for Nene and Linna. I don't especially like the new character design for Priss, but I wasn't crazy about the old one, either, and never understood what fanboys saw in her. I like the new Sylia character design, but don't like the way the designers have dressed her: she runs around in a bustier exposing astonishing amounts of cleavage for most of the show. Huh? Sylia is a scientist, what's she doing dressing like a rock 'n' roll slut? Is it because she's the owner of a lingerie store? Nope, not buying it. Oh, I enjoy watching her, but it doesn't make any sense in terms of her character. Priss also wears a bustier and shows off a lot of cleavage, but it doesn't jar, because she's an entertainer, and show biz types are supposed dress provocatively and fashion-forward. Nene and Linna, at least, dress in accordance with their ages, jobs, and personalities.
And speaking of character design, the KS's get new hardsuits halfway through the show, and the designs suck badly. Yo! 2040 design team! Didn't you realize that the point of Sonoda's original hardsuit design was to let cute women look like cute women, even when suited up? The new hardsuits have huge hips, masculine shoulders, minimal chest, about as much mechanical grace as a fork lift, and expose (of all body parts) the wearer's abs and navel. It just looks silly. Was there a navel-fetishist in the design team?
Plot: the new backstory, involving the Stingray family and the origin of the boomers, that ultimately becomes the main—actually only—plotline, is pretty good, but there should have been more of it. Substantial hunks of the show are mere filler. For example, in the second half, two whole episodes are spent with Nene and some AD Police executives trapped in the AD Police HQ tower, against a horde of advancing boomers. It's part of the plot, but it could and should have been taken care of in half an episode or less, not stretched out for two. There are a number of other episodes which just don't accomplish anything in terms of advancing plot, theme or character. Meanwhile, issues such as the Leon/Priss romance get shortchanged, and the the important theme of the merging of man and machine as a solution to stalled human evolution gets barely mentioned in the closing minutes, when it could have been used to enrich the entire meaning of the show. The plotting of the show feels rushed, as though the writers didn't have the time to properly fit the plot elements to the time allotted, or the thematic elements to the plot.
Technical issues: the DVD's are well produced. The transfer is as sharp as any DVD transfer I've seen. It's much better than the Animeigo transfer of the original OAV's, which shouldn't be surprising, as the OAV's are of mid-80's vintage, and the original media are getting old. The sound track is good, and there seems to be an LFE track in the Dolby Digital mix, which does good things with my sub-woofer. ^^ In my opinion the music is nowhere near as good—or as plentiful—as the music of the original OAV's.
[Update, 7/10: I happened to watch two episodes of the Card Captor Sakura DVD's a few hours after finishing 2040, and CCS is a noticeably softer transfer, which I hadn't noticed until watching 2040. Warning! Whatever the problems with the BGC: 2040 show itself, the DVD transfer is gorgeous, and may make you less satisfied with your other anime DVD's. Props to ADV, which apparently taken the lessons of the first Eva DVD to heart.]
This has been a fairly critical review. I don't want to leave the impression that I didn't like this show. I did like it, but it's a good show, not a great one. It has no fully developed theme, much of the action seems not to accomplish anything, and with the exception of Linna in the first half of the show, the character development is superficial.
In closing, one final note: this is clearly a post-Evangelion product. Eva seems to have changed the mecha genre forever, and hardsuits are mecha. Galatea bears a strong resemblance to Rei/Lilith, and the idea that mecha may have their own souls and may pose a challenge, or even a danger to their owners, is present here. I've also been watching Gasaraki, another obviously post-Eva product, which so far—I'm about at the middle of the show—is more satisfying than BGC: 2040. I hope to post a review sometime soon.