"My guess is that if they manage to get a positive ruling in Europe, they'll somehow try to use that as case for US courts." That's exactly what they have done

"My guess is that if they manage to get a positive ruling in Europe, they'll somehow try to use that as case for US courts." That's exactly what they have done, they sued a Chinese company that was making knock-off Strat copies and selling them in Germany. Fender sued them, the Chinese company was a no show and Fender took that as a win to go after PRS who is selling a John Mayer Strat style guitar.