Story: The story in another is very good but can be confusing at times. The fact that another student (hence the name of the anime which I thought was clever) was in the class and that the rest of the students would die every so often just by acknowledging that there was an extra student in the class was a pretty cool idea, it kept you on the edge of your seat wondering who will die next. But was annoying when there's a character who you thought would be a main character ends up dying like early on and makes you think, well crap that was disapointing. And the ending went a bit weird; like how it was kouchi's aunt who was the extra person (kouichi is the main male protagonist). It would have better if it was someone like izumi was the extra student or Teshigawara or even kouichi himself, but none the less the crazy blood bath battle at the end between the students was a very nice touch.
Animation: The Animation is beautifully designed, especially the gruesome deaths. And makes you cringe because they were so horrific, and the amount of blood from each death was crazy. P.A. Works which is the studio that did another has also done Angle Beats, Tari Tari, True tears and is known to be good with the animation. But maybe it was a bit much not that it's a problem, but they really went all out to make the characters die as horrifically as possible which I personally love.
Sound: The opening is very fitting for the anime it was mysterious and dark, which fits the anime to a t. the ending theme is also good not as good as the opening, but still suits the anime. I've watched the anime in dubbed and subbed. The voices in dubbed were ok some of them didn't fit their characters but there were 1 or 2 voices you would recognise. The subbed version I personally think was better for the voices, but if you don't like reading subtitles or you're not good at reading just stick to the dubbed it's not really that much different.
Characters: They didn't use a wide range of character personalities, but at least they were interesting. I liked the relationship kouichi shared with the students especially with Mei, but honestly there's not much to say about the characters except that Mei was probably the most interesting.
Overall: Another is a really good anime and I highly recommend it to them who really love horror anime's like myself, deffinitely try it out.