Here is the time I spent learning the two Japanese syllabaries
ひら� and カタカナ.
I useda book called Remembering the Kana by Heisig. They use a very fast
method of teaching, as you can see.

HIRAGANA :
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Time : lesson 1 : 14 min
      lesson 2 : 16 min
      lesson 3 : 16 min
      lesson 4 : 10 min
      lesson 5 : 16 min
      lesson 6 : 24 min

Total           : 96 min = 1h 36 min

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KATAKANA :
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Time : lesson 1 : 8 min
      lesson 2 : 4 min
      lesson 3 : 12 min
      lesson 4 : 20 min ?
      lesson 5 : 20 min
      lesson 6 : 17 min

Total           : 81 min = 1h 21min