Alright, so I've been looking around for a particular answer to this question, and I just haven't been able to find anything specific enough for what I'm asking. Let me set the scenario up for you.
-My old 3DS XL is broken beyond repair
-I plan to go out this/next month, and buy a new one (or potentially get the N3DS XL, depending on the answer to my question.)
Now, my question is this: Will the PKHex exploit work for a New (Old) 3DS XL (Note: I am NOT referring to the N3DS XL when I ask this, I already know it won't work for that.) or will the store bought Old 3DS XL's already be upgraded to the current firmware?