I haven't heard any wrong information here.
The reason we typically [initially] try to talk people out of Triples is that the first thing they ask is: "where do I set the knobs?"
We can get you really close, but in reality every car, every driver, every track is a little different. Hence the adjustment capacity.
If we knew precisely where to set everyones shock adjustments beforehand, we would just build that valving into the shock and there would be no need for adjustment
There is NO downside to the triples except [for some] the price. The triple adjustable shock is a powerful tuning tool. Powerful tools cost money. Do you need that powerful tool? Will the single adjustable do everything you need it to do? Only you can decide. You have done the appropriate thing...ask questions of unbiased and experienced users.
Personally, if I cannot make a definitive decision [after gathering as many facts as possible] I typically lean toward the bigger/badder/more expensive unit. I've rarely been disappointed.