Well, I've had a long journey finding information management product that I like.
I have the following criteria:
1) Ease of adding various kinds of data
2) Ease of finding it
3) Ability to access and edit your info across various systems and devices. Especially Windows - iOS - Android, but Linux is a plus.
4) An online client is a bonus, for when I have to access my data from a locked down station at work
5) Ability to access data offline
6) Planning tools
7) Organized structure
8) Low cost or better else free.
9) Secure (ability to encrypt your data individually)
So in my experience:
A. Evernote - great on ##1, 2, 3 ,4, somewhat good on 8 if you accept the limitations of a free version. #9 was unavailable in a free version, don't know about paid one. A way around this would be to encrypt your data via a 3rd party tool (e.g. a KeePass database, or just inside an AES encrypted zip file if it's something not super sensitive - like a credit card statement) and then upload it. But couldn't get past #6 and 7. I had a huge steaming pile of data that I didn't even know about and I felt lost, even with all the tagging.
B. OneNote - this is what I am using now, after Microsoft started putting some real effort into pushing it across platforms. Kudos to them, they did some great work especially on iOS client. It's very well done. Android client is OK, good features but I don't quite like the interface. Handwriting is very useful, although I prefer other apps for that. And of course there's their web client. To me ON has all of the advantages of EN, + great #7, #5, #9 and some ability for #6. And the Outlook integration is good.
C. Before committing to OneNote, I used a mind mapping approach - a free Xmind client on Windows, a paid ($9 or so) iThoughs apps on iOS, and a free version of Mindmeister on Android. The strongest part of this approach was #6, planning. There's simply no better way to plan your project than using a mind map, especially with Xmind and iThought's ability to zoom in on various topics. #9 would be done via same 3rd party approach (although the paid version of Xmind has encryption). As a data gathering tool it was also decent, although there were several major reasons I gave up on it: no advance search / filtering on the desktop unless I paid for a full blown Xmind client (although iThoughts did provide good search), no search inside PDF files, no attachments access on Android (although I didn't spend enough time trying to find a better Android client), and no online cloud client. However as I said, the planning feature and organizational features were great and even better than Onenote's.
D. This is kind of an obvious and easiest solution that for some reason most people seem to not get. Google Drive or OneDrive. Just save your documents there. You get OCR search inside PDFs and jpegs, you get organizational structure via file folders, and you get offline abilities. And obviously it's a cross platform solution since it can be accessed on any web connected device. Same approach to encryption - encrypt it before you upload it. If I ever start having problems with ON I will most likely just move all my info to OneDrive (only because I prefer Online Office to Google Docs).