I've used this phone company for many years and have found them to be just fine. Often I've been to this office to pay a monthly bill or get my phone number changed. They once charged me $35.00 to change my home phone number, but my cell phone company did it for free. So, whatever that's worth.
One thing you should never do is change you long distance service from Sprint to MCI or anyone else. Even though they pay you for the change, you will be paying them back in the long run. They have ways of charging you all sorts of stupid fees. It's best to just leave it alone and use Sprint for both your local and long distance. Plus, you only get one bill that way instead of two, one with Sprint for local and MCI for long distance. It's a hassle that's not worth it.