please stop preaching the security of a chained algo. chained algos are only as strong as their weakest link so if one of the algost piled on top of eachother in x11 breaks the whole chain breaks.
So Quark is 6 times more vulnerable than, say, Bitcoin?
Well yes if that is true it is true...but then x11 is 11 times more vulnerable.

Stop side tracking to coins specifically.
the block time of dark being longer gives longer attack time or not? i don't know?
All you need to do is give one ONE benefit of x11 that clearly goes beyond what no other algo we have had before offers? it really can't get any more simple than that.
State it hear just one simple line of text explaining something about x11 that puts it clearly above all other methods. Then we can analyse it. If true then x11 is the one to go for.