I've started reading eBooks in 2000 on Pocket PCs. I've stopped in 2005 for some time. In 2007, I wanted to re-start. Pocket PCs more or less are "dead", so I've googled for "ebook reader" and found "Mobileread".
#1: I've decided for iRex iLiad because of the posts I've found here. My iLiad was stolen in 2008, so I HAD to re-order it.
#2: Having been a huge fan of eInk already, I HAD to order the Sony 505 in parallel to my 2nd iLiad.
#3: Having the Sony 505, of course I HAD to go for the Sony 700.
#4: I've read great reviews for the Cybook Gen3 and (because of iLiad) already had owned lots of Mobipocket books.
#5: The Bebook I chose because of the biggest variance of formats so far.
#6: The iRex 1000s seemed to be a logical successor for the iRex iLiad.
#7: I'm an admirer of Amazon's success and wanted to see for myself.
#8: Loving the Kindle 2, I HAD to go for the Kindle DX as well.
My reading habits fluctuate quite heavily. Sometimes, I'm reading one book per day, sometimes I don't read any book at all for weeks.
So far, I've bought roughly:
So, actually my invest in the readers isn't that important, comparing to the invest in books.
Usually, I purchase the books I intend to read.