Prepaid phones

We have had a contract with AT&T for at least 10 years. We have four phones on our family plan and are paying about $120 a month.

I have heard about prepay phones but never really looked into them. Recently we have been looking around for other options because it irks me to pay that much each month for a phone!

We are very light users. We each use less than 100 minutes per month. We figure people can reach us at home because nothing is usually that important that it can't wait until we get home. However we do like the convenience of having a cell phone around.

I just found out that I can get a T-Mobile prepaid phone for $20. Pay $100 for 1000 minutes and not have to renew my minutes again for 365 days. With that amount of minutes, it will last me an entire year. I can pay $100 a year instead of $120 a month. Where has my head been??? I am so upset that I never checked into this. I'll quickly get over it though because we will be saving money. :)

So overall, it is a higher cost up front because we have to get a phone and minutes for everyone (only need three now though) but it's worth it. Combine that with our new Google voice number and we are all set. Oh, one more thing. We get to keep our same phone numbers because we just use the sim card from the prepay phone to our old phones and
transfer over the numbers.

Do any of you primarily use a prepaid phone due to low usage? Pros and cons?