Japanese language schools in Tokyo?

I've been thinking about enrolling a Japanese language school in Tokyo from spring of next year.
I did some research and found some interesting options such as ALA, ARC, Tokyo Galaxy, Shibuya Gaigo Gakuin and Shinjuku Japanese Language Institute, but also heard pretty bad comments about all of them.
Anyone here who knows someone that studied in any of these schools? Or even anyone who has studied there and can give me their opinion first-hand?

Thank you in advance!

I didnft go to any of these (I went to Naganuma school in Shibuya) but before deciding on the school I visited a number and did a trial lesson. Finally for me if was between KAI in Shinokubo and Naganuma.

However the one you cite in Shinjuku was one of the most miserable hour of my life. I went for a trial lesson, the group was big (also at Naganuma though group sizes are normally about 14), but the students were totally unruly and the teacher did not do anything to discipline them. There was a noise level that was hard to endure for a single hour. I couldnft have spent there more time.

An other school (not on your list) which I know is good because my husband and also a friend of us went) is Coto. They are much more into shorter courses (1-2 months) and much more towards western foreigners. Main emphasis there is speaking. While at Naganuma there isnft a lot of time to speak. There emphasis is on grammar and reading.
From the trial lesson I did I had the impression that KAI was somewhere in between.

Enjoy studying Japanese in Tokyo.

Btw, if it doesnft need to be Tokyo, there is a well renown in Fukuoka. Where also rent will be cheaper.