I got the mono box and it is really incredible too...and like Barry said, the new stereo remasters are really stunning! I'm getting the stereos individually since the mono box was pretty expensive. I've got six of those stereos now. I just can't believe how excellant the sound is. The Abbey Road sounds better than my original UK LP, and my '70's blue box collection LP.
If you are a Beatles fan, both stereo and mono are great to have. At this point he mono set is very limited so if you really want now is the time...the stereos are going to be around for a long time.
For those wondering about the mono box, the transfers are excellant, and sound like my original UK mono LPs. And the packaging (the mono boxes were made in Japan) is very beautiful, each album a perfect little minutature LP. Opengates reproduced, flipback sleeves, with all cds in the Japanese inner plastic protective sleeves, the original LP inner sleeves reproduced (even the Sgt. Pepper psychadelic one), all the artwork in the White album (poster and four Beatles pics), all housed in the individual plastic resealable jackets. Magical Mystery Tour with inner booklet!
--Todd