Summary: Continuing immediately from where the first half left off, the Fourth Holy Grail War wages on and seven participants still stand and, along with their servants, are fighting for the chance to use the wish-granting Holy Grail. Some of them have clear plans, some plan on using it for another purpose, and still others have no plan at all yet still fight for the entertainment this war brings them. But in a set-up like this where there can be only one pair left at the end not many characters have happy fates waiting for them.
The Good: I rather unexpectedly became quite attached to some of the characters in this show, mostly side characters admittedly, and every character who either survived the show or came close underwent a good deal of character development in this half. I was sad to see that Saber didn't get as much as I had hoped (which I suspect is because it all originally happened in Fate/Stay Night, the one problem with prologues is that they are bound by things such as that and F/Z had a few other odd character moments arise from that) but other than that I was satisfied. I do wish they had touched more on the history of the Grail War itself (which I read up some online which both explained a lot of things and was just plain interesting) but I suspect that's another thing that was covered in F/SN so couldn't really be dealt with here.
The Bad: To agree with quite a few other people on the internet, the two episode Kiritsugu flashback was much to long but my even greater problem was that I actually didn't know that he WAS the main character until I went "geeze, he's in the opening A LOT, like, more than anyone else." The first half of the show had made me think the story was going to focus more-or-less equally on all seven pairs, not that it's very much Kiritsugu's story, and that's a rather large narrative failing, I believe it is made clearer in the novel where he has internal narration, which also appears to make him more sympathetic earlier on. That lack of internal narration also made it much harder to, well, not be bored whenever Kirei was on screen. To explain why his character bored me would be dangerously close to spoilers but he's of an archetype I'm not particularly fond of so, while he did make some great looking fight scenes possible, in the end I just didn't care about his character at all.
The Audio: There were new opening and closing themes but no new major characters (and obviously the same music composer) so not much changed. I didn't like the opening and closing themes as much as I liked the original ones and several of the actors really had a chance to prove that they had range but other than that there's not much else to say that I haven't already said.
The Visuals: As expected, the second half of the show looks just as good as the first half and all of the fight scenes are stunning to look at. While I still liked the fight in The Legend of Korra a bit more for their choreography the fights here were a close second for their fluidity and just plain old visual interest. There were also quite a lot of them (I'd ask where UFOtable got the money and then I remember how many sets of the first half they sold) and many of them incorporated CGI very well (which sounds like a no-brainer for American animation but a lot of series in Japan are still hand-drawn and I've seen a bit of hostility to companies using CGI in these circumstances). Actually, in addition to making me more curious about the rest of the Fate franchise, all of the art here has made me more and more interested in UFOtable's other well-known series, Garden of Sinners, and it's always impressive when a studio leaves such an impression on a viewer that they want to see other, completely unconnected* productions they have made.
So, I'm not getting the second box set since I don't have $400 to spend, honestly I probably wouldn't even if I did, but I do hope Aniplex puts out a Region 1 priced set in the future (and I've heard rumors that some of the extras on the original set weren't subtitled so if any of those were included I hope that's fixed).
*okay, semi-connected in the sense that they're apparently in alternate universes but in the Type-Moon mega-verse overall, or something like that