I am quite familiar with E. nitens. They are beautiful large trees with long leaves (up to 12"). I took down what was probably the largest E. niphophila in Canada about 2 years ago. It was 50' + high. I had shaped it to be single trunked with a very round crown. Everyone remarked on how nice it was. I removed it because it was hanging over my driveway and a neighbours property and was always dropping something (bark/leaves/seed pods/flowers). The neighbour has a heart condition and the mess it left on his lawn and gardens was more than he could handle. He asked me to prune it back, but that would have just delayed the inevitable and ruined the look. The Western Gardener book said this species grows up to 25', which is why I chose it. Had it stayed within that size I would still have it. It's annoying they can get it that wrong. You have the space for such trees. I only have an average sized city lot.