12C Platinum vs. 48GX vs. 50g (Speed Test)

[JDW]

Would any of you know of complex and time consuming calculation that could be fairly easily run on the 12C Platinum, 50g and 48GX, for the purpose of doing a speed comparison between the 3 calculators?

I found an IRR example on page 63 of this PDF, but I'm not sure how to run it on my 50g and 48GX. Getting the IRR in that example takes just under 5 seconds on the 12C Platinum (purchased in 2015). That's barely long enough to make a good comparison with the 50g.

What I'd like to see is a calculation that would take at least 15 seconds on the 12C Platinum, which would make it easier to see the speed differences with the 48GX and 50g. Obviously, the 48GX would be slower than the Platinum but the 50g would be many times faster.

One more somewhat unrelated question... The back of the packaging on my 12C Platinum has a Copyright date of 2015, and the barcode date shows 03/14/19. It says Made in Philippines on the back of the calculator. I assume this is the newest variant of the Platinum. The keypad seems fine to me with good tactile feedback. I've read that there were good and bad keypads in the 12C series through the years. Does anyone know if my "2015 and newer" variant is considered one of the better keypads or how it compares with the 1981 original 12C?

Thank you!