Here in NZ most roofs are corrugated iron, and people love the sound of rain on them. Different cultures...

There is another good reason for our love affair with iron - we get a lot of earthquakes. An iron roof provides a lot of structural bracing, and it's negligible weight provides much less moment than slate or tile alternatives.

Corrugated is only one type. Lots of places around here (Seattle) have metal shingles, and I've never noticed noise when in them in the rain. Perhaps it has to do with how they are mounted and, of course, it rarely rains hard here. It mostly just drips.

Metal roofs are light, long lasting, do not support insects, and don't burn.

This is true, but I've found that there is nothing quite like sleeping under the oddly soothing sound of heavy rain slamming against corrugated iron roofs.

If you factor in a couple thicknesses of plywood, insulation between your rafters and/or roof stringers, and the sheetrock on the ceilings of your rooms, that deadens out most of the noise.