As someone said further down in the comments, go do Arenajunkies.com and check out all the top rogues, they are ALL using Engi goggles because it's no longer a choice, but almost mandatory to do well against ANY other rogue that are also wearing those googles, especially humans/night elf rogues, there is no choice in the matter, if you wanted to do well you needed it.

If you aren't doing Arena with a rogue or as a rogue in the 2200+ brackets you will never understand the competitive advantage those goggles bring vs other rogues, I can bet 100% that most people that are enforcing 'choice' is on the line of "lol 1 level of stealth detect? sure thats imbalanced", well, it is, looking at it from the view of a bystander it may not be big but from a competitive view it is stupidly overpowered when it comes to Rogue vs Rogue and getting the sap on the other rogue

For any class that isn't a rogue using these goggles the nerf is almost insignificant, classes other than rogues (and maybe feral druids?) have limited base stealth detect, adding an extra level to that rarely ever makes a difference, but for a Rogue vs Rogue situation it's pretty game breaking.

But i don't expect anyone to read this, I'm fairly sure people already in a state of "OMG WHY BUFF ROGUES FFS BLIZZ" and can't see past the fact that it was actually addressing Rogue vs Rogue imbalance and has little to no effect on Rogue vs Other Class, but so is the way of ignorance.