I'm lazy, and seriously, why do extra work? That said, I've been looking at some of the "instant" wheel cleaners for the daisy wheels on my '90. I happen to have a spray bottle of Meguiar's Gold Class Instant Wheel Cleaner (got it for free so I have it) and I'm willing to give that a shot. However, the bottle warns to not use it on non-coated wheels.
So, um, are the daisy wheels "coated"? I would think they would be, and I like like the spray on/hose off/wipe dry concept. And they OEM, so I can't imagine Mazda would put anything out there that's "fragile." But I really don't want to mess them up, either, because I'm not cheap but I have other things I'd rather spend my largess on than replacing formerly-good wheels.
Daisy wheels are painted, yes. If you're concerned about the chemicals, try Simple Green and a soft round brush attachment on your power driver (and wear goggles).
My two cents.
2008 Copper Red
Sorry for the delay in getting back on this. I tried using Meguiar's spray-in/hose-off stuff in a squirt bottle. It worked as advertised, though at first it didn't look like it did on the "pockets" by the spokes. I treated it, sprayed it off and then reapplied it to the parts that still looked a little dirty.
It still didn't look as good as I think it should have but after it dried and after I drove it a while, they look almost new. I highly recommend Meguier's wheel cleaner. Unless you have fun scrubbing and scrubbing.
Now, out to take my first shot and clay barring.