I've used the cups, they're OK but won't stand up to freezing.Good to know, as you can see I have tried the same type or nipples as yours but decided to go with the flip over type. Now the nipple ones along with cups are up in the rafters along with some homemade feeders.
My freezing climate is why I ended up with HN's,
and they work just fine all year around and in numerous situations.
Look at my 'Articles', several on HN's there.