not a problem, on a side note the only reason i ran the RUU was because my bluetooth stopped working. it worked on the odex version but when i flashed the deodex of 4.3 it stopped. (clean flash btw) so i swapped back to the odex version and it still didnt work. RUU'd and still nothing. taken it back to sprint in the morning.
but yes you can switch back to older firmware fine with no problems.
This is just an FYI for anyone who wants to use VipeRUU, but can't get it to work, or doesn't have access to a computer. If you open the zip file, you will find a file called "rom.zip." If you change this filename to PJ75IMG.zip, and place it on the root of your ext sd card, it will run the entire RUU as normal.
It also leaves your bootloader unlocked. I used this to return back to stock (in appearance) and get Sprint to order my a new phone. Now, I'm back on Sense 5, fully restored in under an hour (without a nandroid).
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