That one stays pretty small. It rarely gets wider than a foot and the spines don't seem extra pointy. They don't hold up as well as some of them. I've rotted a couple of them but once I figured that didn't want it as wet, I've kept mine now for about 6 years.
Even though this is not an extra picky one, like maybe D. delicata, one of the secrets to these is that if you look at how they grow in Brazil, they are on sides of hills and they sit at an angle, which makes excess moisture drain off the plant and not getting caught in the cup.
OK, I am Editing , I just noticed I haven't mentioned trichomes in detail yet in this topic. Usually with silver dyckias, they feel a little fuzzy on the tops of the leaves. This is a three dimensional organ called a trichrome gland that is used to absorb moisture. There are many species that live on cliffs, or on sides of various sized mountains that don't experience actual rain for a good six months. What they do is get fog coming up from the lower elevations, the trichrome glands absorb the fog, and that is how that get watered. At the same time, many of these species don't want to get real wet in cultivation. A term for a mass of these glands is called scurfing. You can see there is some scurfing on that ML hybrid. This is another reason why I call some of these landscape dyckias, because you don't want something picky when you pit them in the landscape. Now in a nice rounded rock garden these would be perfect. I think a nice little dyckia garden could be done with a 10 to 12 foot circle mounded about 3 to 4 feet tall. You can plant them all the way around and they are displayed where you can see every single plant from several feet away.