Well, the custom firmware seems to be a little poorer that the standard one. For example with that one you can browse the Internet only with a little trick (you must upload an html file with a hyperlink and then click it), because a link to the browser in menus is missing.
Note taking seems to be a little messy, I don't like it too much, and indeed I'm not interested in it.
When the warranty will expire, I'm going to try to install one of custom firmware I saw in this forum. The hardware seems to be exactly the same, so I think that it can be done.
If you have some questions feel free to ask, also via PM if you preferer. I can manage to buy one for you and send it to UK.
PS: the firmware have both italian and english languages.