We have Personal, but we hate it. My husband's voicemail didn't start working until about 6 months into using it, the coverage is bad, and often we can't get into the voicemail system (about 30% of the time). I'm not going to go through getting another phone right now, but I wouldn't start with Personal again.
And in terms of trying another SIM card, youc an do that, but only with an open phone, which is much more expensive (unless you buy it on the black market). If you want to buy the cheap, pay-as-you-go phone, you have to purchase it dedicated to one provider.