Are there any compatibility issues if I decide to get this FD?I never had Sram, I know rear derailleurs are not compatible with Shimano shifters due to actuation ratio, but does this apply to Front derailleurs as well? Also, itīs a 9 sp Front derailleur and I plan to use it with an 8 sp casette.Do you think the chain will rub against the FD cage?

Thank you.

yes the chain may rub. should be ok otherwise. the 10spd stuff is not compatible

Front derailleurs don't have the pull ratio compatibility issues of rear derailleurs.