Who has Sony Ericsson Z310a or Sony Ericsson W580i CELL PHONE?

I'm thinking of buying one of these phones but i don't know which one is better. I really care about calendars and reminders because i have a busy life and i want a schedule on my phone. If there are other CHEAP phones you would prefer, but they have to be cingular. I want my type of phone like reminder AND voice dialing, voice recording so that can be a ringtone. If anyone has thses kind of cellphones, please tell me what they have

thanks!