6% armor means a lot when you don't have magic bubbles though
Guard relies on hate rather than dps and has a lot of survivability tools, it is a very sturdy tank. DT doesn't have the survivability tools and relies on leeching life as he hits. It can be very defensive though, with a class-specific pet that takes aggro from a boss or mob for a few seconds, or it can also be very aggressive on talisman spec doing the most dps of all the tanks even in defensive stance.
I think DT is the most versatile of the three tanks, because you can tank or dps without really having to switch spec, unlike conq, and guard can only really tank (its dps is too low).
DT is the most boring class in game beside ranger, I'd go with conq (brute) or guard (s&s) no matter what. Their game play is way more engaging and better.
You'll notice I've pointed out 'brute' and 's&s', that is because carnage conq and pole arm guardians are as garbage to play as tali DT is. The difference being that polearm guard guardian dps wise is, by far, the worst out of the 3.
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On a side note I'd like to add that you can "tank" everything in game as carnage conq. It will be hard for you, your healer will struggle, 90% of the players won't accept it, but you can (could).
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