It all depends on your skill lvl and what your strategies are. A good kirby can beat a jiggs and a good jiggs can beat a kirby. Even though jiggs has that sexi combo against kirby, which is his bread n' butter, you guys forgot that there is still DI XD. Using a keyboard, you can escape jiggs combos easily, just watch out for the usmash. What gives kirby the advantage is that he doesn't need to combo to kill you, which jiggs is highly reliant on. So you can kill jiggs without worrying bout her DI'ing outta your moves. Just do a fsmash or dair. Plus, for some odd reason, DI'ing outta jiggs dair is really effective while DI'ing outta kirby's dair is just not as effective because of it's power and spikage, there aren't as much DI frames in it. Plus, Kirby's got the broken hitboxes while Jiggs doesn't. This is all in my opinion guys, so don't worry. It all just comes down to skill and strategies/mindgames.