Anyone else hate coil on plug?

[MikHalifax]

I have an '01 E150:
5.4L V8
107,000

My van is randomly missing again, through the RPM range. Seems to happen after the van has warmed up and has been shut off for a few minutes and restarted.

Had all the plugs replaced last year when #7 cylinder coil was misfiring like crazy. Since then I've had to replace the coil on #5 as well. Does anyone else think this is one of the worst designs ever, especially on the E-series?

I also wish it would trip an engine code sooner, took it to the mechanic and he said it would have to misfire 18000 times before tripping a code. That's missing a LONG time.

Ok rant's done. I had a lot of condensation in the plug chamber when I changed the #5. I think the boot was cracked. But I have a suspicion that it's the same cylinder misfiring again. I put the dielectric grease on both ends of the terminal. Any other suggestions if it's that cylinder again?