I have to give 5 stars because this phone has all I need: I used to carry two phones, one for each operator, now I only carry this. I don't use mobile phones to listen to music or access the net, so I didn't even try these functions, sorry. I only use them for voice calls, text messages and calendar, and regarding those functions I'm totally satisfied. It will receive incoming calls dialled to either SIM card, and originate calls from one of them, preset by you. You can preset the other card anytime. Menus and options are loosely based on Nokia's, but with improvements. E.g.: I can set it to give the sound of a new message every so minutes, instead of only when it's received. The calendar also has a better outlook, with coloured codes for different types of appointment. First battery charge lasted 5 days, with over an hour of voice calls.
Short comes: when you change the preset card for originating calls it restarts the phone (but doesn't ask again for the SIM codes), which takes about a minute. Also the battery indicator is misleading: rapidly shows low levels of capacity even though it still has several days worth left.