Such passwords are certainly secure, but it's a pain to have to carry Keepass/other programs around when using other computers. I think I've found a happy medium by memorizing a simple password-generation function in my scripting language of choice. It produces sufficiently strong passwords, and if you're stranded without Keepass you can still generate them using a local interpreter or a site like codepad.org.
If you can sync your password safe aoftware to your phone, that pretty much solves that problem, at least for me.
(I also rely on having one of my phones or my iPad with me anytime I need secure access to any account of mine, 'cause I use two factor auth using TOTP tokens for places that support it like Google, Amazon, and Dropbox)
This doesn't work because there are conflicting rules out there about what a password should look like. Less than X chars, more than X chars, must contain certain chars, must'n contain certain chars...
I use KeePass, with a copy (via dropbox) on my smartphone for when I'm not at my own computer.
My bank actually limits passwords to a maximum of 10 characters. Drives me bonkers because it prohibits my normal use of the Stanford PwdHash. Many other sites have "helpful" rules that get in the way as well. Frustrating.
