Elex Pads on the Clear do
not sound the same as the Clear pads on the Clear, nor do they measure the same. The general shape of their frequency response is very similar, but Elex pads on the Clear result in them sounding brighter and less even in the mids, along with a slight loss of bass energy and an odd tendencey to "unsettle" some female vocals.
Here's a plot of just the Clear and the Clear with the Elex pads, uncompensated (RAW), with the vertical axis expanded to more precisely show the differences:
And the same plot, but with HEQ compensation:
The literal differences don't look that large, but they're enough to tell that you're not listening to the same thing, even just swapping them back and forth immediately - especially if you listen to a decently wide range of genres.
Now, there are enough differences in hearing response, rigs, and personal preferences that some people might actually prefer the Clear with the Elex pads on them.
I am
not one of them, however.
I didn't really care for the feel of the Elex pads either.
Incidentally, measurements were all done at the same time:
Finally, I ran the Focal Clears in my office rig for a little over a year. Neither the pads nor the headband ever discolored or stained. And the one person I know that managed to splash Pepsi on his set was able to clean them up just fine using "Sonax" (which was a couple of days after he splashed them). If they looked any different to mine after he did that, I couldn't tell - there was no issue with lint or pilling.