Plug Wires/Engine Misfire

A few days ago my '96 Discovery started misfiring. I checked the plug wires, one was loose on the coil pack. Tightened everything up, no misfires for about 70 miles worth of driving. I started getting them again, repeated process of pulling and replacing them, no misfires for another 70 or so miles. Happened a third time last night so now it's time for new plug wires. Throughout all this the check engine light did not come on until last night. I'm going to take it to Advance Auto to see what codes it's throwing but it seems pretty clear to me that I need new plug wires, right?

That being the case it looks like STI come highly reccomended, so for my '96 with the 4.0 I need the STI wires part number RCIWS663 from British Parts of Utah, right?

Thanks guys.