I agree with BladeTH that it would be helpful if there was an option to turn off multiple targets. My problem is that not only is it difficult inputting them on a game-pad, but I also have difficulty even seeing and responding to them quickly enough.
I am experienced with the Project Diva console games and my skill level is high enough to clear most songs on hard, but I am not improving on clearing the multiple targets.
Is it possible you could release that option in a future update, or as a mod?

I can fix this problem, i use ps2 controller
the program u need is : X-padder

by using this program, u can use D-pad to press circle, cross, triangle and square
You can also set one button on controller to press 4 buttons : circle, cross, triangle and square, it works for 3,2,1 buttons too ( i set L2 and R2 button to press 4 buttons)

it doesn't work well like ac controller, but u don't feel upset anymore when it comes

the only problem i have when i use ps controller is sometimes the buttons appear closely, for example, you have a string of circle , and they appear very closely, no matter how fast u press, using D-pad and circle, cross, triangle and square buttons, it just doesn't work. I hope some day Admin can fix this