STAT variable or memory bit in an S7 safety function block

Question for the Siemens experts.

In an S7 safety function block, I'm adding two safety function blocks for emergency stops (F_ESTOP1, FB215) into the function block. I saw a Siemens example where they used local STAT variables as the output of the function block to enable logic in other parts of the block.

What's the advantage of using a local STAT variable over a memory bit?
In a safety program I'm pretty sure it's because the memory bit is not considered safety I/O (it highlights red in the safety function block), where the STAT variable is a part of the safety function block and its instance datablock.

What would the advantage be of using a STAT variable instead of a memory bit in a standard program? Retentivity?

Using a Stat variable makes it easy to manage the data. Markers tend to get messy quickly and do allow for reusable blocks.
Keep everything self contained in a FB by using Stats or Temps.

My 2 cents.

M Flags and STAT's can be accessed anywhere in the program, the big advantage of the STAT is is the fact that the FB can be called numerous times, so you can have a self contained sub-routine for a specific type of equipment.

If you have 3 of the same thing, then the block can be called 3 times and the internal memory (STAT) is unique for each call.

As Mike says above, even when not called multiple times it contains the code nicely.

I rarely use M flags for anything other than common items, like timed pulses, always on/off flags, etc.

OK. Thanks.