For me, the key benefit of Mint and BillGuard is that they link to my bank account and categorize my transactions automatically. I have never been disciplined enough to enter transactions by hand.
The sad thing is that the main risk is that banks use the same token for Read access as ReadWrite access to your accounts. There's no need for that; OAuth solved this problem years ago.
I use YNAB and I really like going through my transactions manually. I import them from QFX or what-have-you, and then manually confirm them and reconcile. I've found it to be helpful psychologically; I find myself thinking, "ok, that expense seemed great at the time, but am I happy about it now?", which helps me cut down on the kind of spending that I tend to regret.
I used Mint for a long time, and it never helped in any way. I would go look at the summary once or twice a month, think "ok great, all in order", then eventually stop looking at it at all because there was never anything actionable and thus little point in looking.
