[...]This Bach set is an amazing bargain. Clearly the set is geared towards the novice and you'll want to replace individual performances eventually; but much of this material is difficult or impossible to get elsewhere (except as part of one of the two other Complete Bach cycles), and you'd be unlikely to anyway. Plus, there are many very good performances, which alone would make the set worthwhile at this price.
As far as I am concerned, the Hanssler Classics complete set is the best of the complete sets. I've reviewed that one separately. However, it is ten times more expensive, if you can even find it. Your other choice, the Bach 2000 set, contains the Leonhardt-Harnoncourt cycle of Cantatas, which I cannot stand. I agree with Jim Svejda when he noted that Harnoncourt and Leonhards "gleefully take turns mauling the luckless pieces beyond recognition."
One of the saddest facts of musical history is that Bach was not recognized for the genius that he was in his lifetime. His compositions were mostly occasional music that were played once. After his death, they were so little respected that much of the sheet music was sold for scrap paper and about a third of the Cantatas were lost forever. Fortunately we have what we do. That Brilliant Classics has made this wonderful music available at a price that allows a more widespread distribution makes it reason enough to purchase the set.
Brilliant Classics attempted to record the entirety of Bach's remaining compositions on period instruments utilizing the most recent Bach scholarship. 65% of the set are new recordings. The other 35% were licensed from other lables. Now some, like me, much prefer the recordings on modern instruments. I have yet to hear a harpsichord rendition of the Goldberg Variations that is superior to the top performances on piano (although it is a well-known fact that Bach hated the piano, which during his lifetime was little more than a toy). All of the keyboard works on this set are recorded on harpsichord. Pieter-Jan Belder records that Goldberg Variations. It has received fine reviews, but I simply cannot get beyond my prejudices against the harpsichord to comment meaningfully (it is quite lively, though).
That said, and with the reservation that this set is performed with nearly all period instruments, I can recommend it without hesitation at this price.
The Brilliant Classics set has an interesting history. It is based on 5-disc sets of the Cantatas sold at the Krudivat drug store chain in the Netherlands at bargain basement prices (the equivalent of pennies per Cantata). More than 100,000 sets were sold in the Netherlands alone. Pieter Jan Leusink, conductor of Holland Boys Choir and Netherlands Bach Collegium, recorded the Cantatas over a period of 15 months, an insanely short period of time. It is the first digital recording of the Cantatas. There is a consistency of performers in this cycle that is unrivaled, although not all of the performers performed at the same time. Also I find the women singers on the Rilling cycle of Cantatas better than anything a choir of boys can do, despite the unhistorical aspect of such. I doubt that female singers would have shocked Bach--after all, he married one. An interview with Leusink regarding the cycle can be found online.