would this USB cable be ok between my iMac and DAC?
try to get usb cable as short as possible, preferably 1m or below if you can
i was hoping to use a longer USB cable and my .5 meter Kimber PBJs
my computer is in the next room,
will a long cable cause a lot of issues?
It might work, but I'd be worried about dropouts and such seeing as it is right at the maximum rated length for USB. If you can afford to shave off a few feet I would do that just to be safe.
ok, i might be able to go down to 10ft
The USB standard says 5 m max.
At $3.93 I would run the "risk"