a second chance

[Michael.A.H]

hi guys
for some reasons my kobo aura h2o , which i have ordered several weeks ago has been canceled and my money is refounded , it happened also for pocketbook inkpad 840 , which was for my friend , so both of us has been given a second chance to choose an ebook reader .
the main competitors for us are : Amazon Kindle Paperwhite 2015 , Kobo Aura H2O , Pocketbook Sense , Pocketbook Inkpad ( i know some may say wait for the 7.8 inch device from kobo which may be released several months later , but for two reasons we can not wait: 1.the price will not be reasonable 2.we can not wait . )
considering these choices , and the fact that we will be using the device to read PDF books ( and i know that you would say ebook readers are not good devices to read PDFs on them ) and mostly in the daylight . so here comes the questiuon : are these three devices the best one in the market ( considering the price range ) to buy , or are there any other ebook readers , which i should think about theme too ? such as some devices from inkbook or icarus and etc . if these devices are great in their price range , which one should we buy ? i am really into pocketbook inkpad , but as i have read in some reviews , people claim this device to be slow , is it really that slow ? and it has a eInk Pearl display , while other three devices have eInk Carta , are there any major diffrences between eInk Pearl and eInk Carta ?
p.s: is there anyone who has PB840 so they can test to see if it shows arabic and persian books properly ?
Thank You All In Advance