It's a Kingston 8Gb "MicroSD HC" SDC4. I don't know if it's class 2 or not.
Also, does it really make a difference? If the system is thrashing the disk, then all the usage should be in the two internal sdcards. Is that right?
What kind of card would be a good replacement?
Its a class 4 which means the r/w speed should be higher than you are reporting. IMO either your phone can't support any higher speed or something is wrong with the card.
The class of the card does matter and can cause some operations to be slower in comparison to say a class 10 card.
I don't know why your phone is thrashing the card, unlikely normal, but it could be. Other possibilities are issues with the phone software, or issues with the card like partial corruption or bad sectors, even bad pics or vids can cause the system to scan the card too much.
Look in battery stats and see if the media scanner usage is high, this would indicate a corrupt file.
Alternatively, I would test the card for errors. Grab a card tester from Google search, put the card in your PC, copy the entire contents to your PC, run the test program. If no errors, put the card back into the phone and format, then copy back your files.
If errors, get a new card. I have always bought sandisk class 10 from an eBay reputable seller. Read up on the seller wherever you get it from so you don't get a fake card.
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