Diap Dealer have a look at this book on Amazon
http://www.amazon.co.uk/Life-and-Lau...022115&sr=1-14
incase the link doesn't work it's 'Life and Laughing' by Michael McIntyre
Kindle Price £12.98 Paperback £5.99, that's actually more than double. Ok some of it is because there's vat on ebooks but not on hardcopy. At 20% that makes the ex.vat price £10.81 which is 1.8 times the hardcopy price.
If DRM is present then you are paying more than double for something very restrictive compared to a book. If, after paying double, you then found it was Topaz format how would you feel?