If you have your own progress, overwriting it will erase everything. However, you can back up your original save to USB first, then reload it later. The PS3 allows multiple save profiles via different users.
To use a free save file on your PS3, you must typically transfer it from a USB drive and ensure it is compatible with your console's region. j stars victory vs ps3 save data free
If you want to locate a save file today, try these search strings: If you have your own progress, overwriting it
: Provides maximum currency to buy additional items in the J-Point Shop. Completed J-Adventure If you have your own progress