Andy: was playing my strats the last few days too. I was really happy about that, didn't realise how much I missed them. My approach is very different with them, I've taken a couple of pointers from you. Lovely guitars.
BoogieJeff: I have a (more or less) standard JCM800 and find it a little too bright to be used with a strat plugged direct in with a straight cable. The strats I can use like this are loaded with Sinners and Slow Hands. Anything else is too ice picky. I don't know what mods you've done to the JCM, maybe you've had some of the top end rolled off. Myidea of a good strat tone is Rory Gallagher, Uli Jon Roth, Yngwie Malmsteen and Richie Blackmore.
My 'trick' is to copy some of the greats and use a curly cable and a treble booster (Phil Hilborne Fat TB) and then all my strats work like a charm.
If you find strats too bright in general in that JCM I would suggest the Slow Hand set as they are a bit darker but still vintagey enough to get the chime. They quack for sure, but maybe not QUACK.
Irish Tours are great 'do anything' pickups. I would hesitate to use them in maple board strat into a stock JCM800. But some people love them with maple boards, so what do I know ;)
I have the slab board set in a veneer board strat, and they do require a bit of external assistance with the JCM, brilliant tone though if you get it right. I agree with Telerocker that they are brigher than Irish Tours, they can be scratchy with hard rock levels of gain. If you run them clean or with just a touch of gain you get all the classic chime and quack you want.
Most likely, the Irish Tour is the right choice for you. It depends how hot you want to go.
Different also if you pluck with fingers or use a pick. I've assumed your more of a pick kind of guy. If you play with fingers, you don't need to worry about too much brightness.