Yes. I vote for wires. My experience is that the wires will fail before the plugs get so bad it misses. And... just the process of replacing plugs is likely to cause "human induced" wire failure. If you run it long it will get all fouled looking, just like that nasty one.
If you want more assurance, you can pull the wires off the coils one at a time, with motor running and IAC unplugged. The miss will either get worse or stay the same. Of course, when the miss does NOT get worse with a wire off, that is one of your bad plugs, wires or coils. I'm a chicken, so I like to use rubber handled pliers and rubber gloves. It will still give you a little tickle when the wire is put back on.
Call me "Sparky."
1993 Red SSE - Bone-Stock except for High Perf. Power Antenna-Original Owner. Less than 130K - Love of my Wife
'05 Magnum R/T Hemi - Bunches of classic VW Beetles... and one "not quite stock."