Ask HN: USD or GBP?

When considering monetising a global business, ie a service that can be used in any country. Has anyone got any experience on whether their local currency works better than charging US Dollars. I hope I'm not generalising too much based on personal experience, but I don't mind paying using dollars - however, I can't speak for our friends across the pond paying using UK Pounds. Has anyone got any experience regarding this they wouldn't mind sharing?