As we are all aware, all tanks are supposed to be equally good if played correctly, however, I'm sure I'm not the only one that has had coincidental experiences with certain classes that might make you think other wise. I want to hear from you.
My favorite tank to heal in dungeons are Blood Death Knights and Guardian Druids, they seem easy and almost all tanks from those two specs I have been paired with require almost no healing whatsoever.
On the other hand, my least favorite tank, to a point that I cringe at the very sight of them in my Vuhdoo panel are Protection Paladins. I'm sure there are good pally tanks out there but they seem to avoid me. It's like they have zero dodge an parry and are to cheap to pop any cooldowns. They take so much damage I throw them everything and they die in an instant. Brewmaster Monks are similar but thankfully I have been paired up with really good ones every now and then.