gaia,
Interesting question. At first my thought was problem what problem certainly these daisies are very much at home in a perennial bed. Then thinking about my own use of this sub shrub I realized the Nipponanthemum nipponicum work best in my shrub border where there is plenty of room for them to slowly mature over the growing season. In my perennial bed I tend to be too impatient to wait for this mid-border plant to mature so I often surround it with annuals and tender perennials and by this time of year it is completely buried.
It's form can be very formal and tidy during a season where many of the plants in my perennial bed tend to be loose and floppy. A classic Companion is Sedum 'Autumn Joy'.
A note for those who may have never grown this plant if at the end of winter you cut it back to about 12" then continue to pinch back as soon as new growth begins and continue to pinch until about mid-summer. kt

I have it in a mixed bed, between a purple cotinus and a baptista, at the top of a stone retaining wall. It flops all over, which I suppose is what you mean about its form, but in that particular spot that's not much of a problem. If I were more vigilant about cutting it back in spring, that would probably help, but it blooms so late as is that I'm always reluctant to take a chance on delaying the flowers to the point that I'll miss them altogether.

I do think the solid mass of clean, slightly glossy foliage and the shrubby form are a good counterpoint in a perennial bed, where sometimes there is little else that's solid-looking and plain green.

Mine also pops up 6 or 8 feet away from the original plant, which in other areas might be more of a problem - this particular bed is a bit wild anyway so I don't mind it here.

My sister grows it as a hedge around her annual cutting garden, which seems like a good alternative, but personally I can see it in a cottage garden, providing a little bit of an anchor.

Thank you both for your thoughts. Today I moved the Montauk into a hillside space among junipers and yews, where it should shine! The issue with the "waiting" was running around my head, I realize - I just couldn't figure out how it would look in mid-July as a garden anchor...though I know in October it'd be fantastic!

I first encountered Montauk Daisies at a friend's and they were growing amongst Raguso roses and thriving well. Pests do not like them. We have a deer tick problem and they help along with