In a situation like that I would usually define a boolean before entering the top loop, and set that true within once a condition is met, causing all the outer loops to break if that condition is true. I can't imagine there would be a major speed difference in some other way of breaking all the loops to jump to a different line of code.

That means once it’s set to true, all the inner loops would need to at least finish that iteration. That could be a huge speed difference at a minimum or a completely wrong implementation.

this means you do a if check each loop, this is bad if you do some say image filter/effect where you work with big loops. end you get some nested if and break inside the code, is much more readable to just jump out.

I would argue that having to do that is not in fact a 'proper' loop. Your way and goto are both workarounds for a missing control flow construct.

For gosub, what's the issue? It is a method call.

Pythons for-loop is not working with boolean, so using one would mean to uglify the code. A goto would simplify the workflow by removing 1-2 lines for each additional loop.

Is that faster than (or comparable to) raising an Error in the inner loop and catching it outside the outer loop?

Internal error bubbling code is slow and can change from release to release. And it's definitely not intended for the job.

probably faster since it was built for this purpose, throwing an error would have to at least create an exception object, then create stack trace and the other setup stuff.

As i said I code for almost 20 years and I only had to use it once so far, but people that maybe work a lot more with stuff that needs a lot of performance might use it much more often.