MOT is a competent film, but not something that I think Argento should be proud of. As other reviewers have pointed out, the rich color palettes and clever cinematography of the early Argento are nearly absent from this film. There is more gore and it is more competently done, but it does not have the desired shock value, since it doesn't seem random and the viewer is not as disoriented as with Argento's earlier films.
The story is satisfactory and fits in with the other two "Mother" films fairly well. The script is mundane and the dialogue doesn't seem to have any passion.
The biggest problems are the casting and acting. Nearly all of the actors start chewing the scenery as soon as they are introduced. Udo Kier is perhaps the worst offender in this respect. Moran Atias, in her final scene, is simply awful...artificial and totally unbelievable.
Which brings us to Asia Argento. What can I say? Her acting can best be described as "often competent." But the lead in a film of this sort has to be more than that. I just never developed any belief in Asia as her character. No belief means no sympathy. No sympathy means no drama, as I'm not really concerned about her.
If you like Argento, or if you've seen the other two "Mother" movies, then you should probably see MOT. If you are looking for an introduction to Argento's work, this is not the place to start.