Completed of course. While ongoing has that advantage of making you look forward to the next chapter, and make you able to come up with theories and discuss them, I take reading a good story in one sitting over waiting patiently each week to a month for a new chapter any day.

[img]http://fc06.deviantart.com/images2/i/2004/05/3/6/I__m_sorry_I_couldn__t_save_you_.jpg[/img]

I only ever read complete ones. I don't like cliffhangers.

[img]http://i1141.photobucket.com/albums/n590/mvobsuna14/ezza%20set/colorsig1.png[/img]

[color=#C6AEC7]Thanks to blueangel06661 for the stock![/color]

I love completed series. Less disappointment than ongoing series that get dropped. However I also like the experience of waiting for a new chapter and reacting to each cliff hanger and such.

I used to read only completed manga. I read an ongoing manga on a whim about 4-5 months back on a whim. I realised how fun cliffhangers were. They give you an opportunity to think, analyse the characters and make up new scenarios while waiting for the next chapter to be released. Since then I have been reading both ongoing and completed ones.

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Mostly completed manga. I read them in a row till the end (online reader).
Only for book releases I prefer ongoing series.