I have the same issue with my Sprint 8703e. Constantly switching from 1X to 1XEV to 1x. It's especially bad near my home. I disagree with the previous replies claiming it is a reception issue. I have had numerous other Sprint data-capable phones and never had problems like this at my house. I believe it is one of two things (probably a combination).

1. Radio receiver has poor discrimination performance and cannot pick-out and hold a signal for very long.

2. Software that forces use of a very weak 1X Sprint signal when a much stronger 1XEV signal from another carrier (Alltel in my case) is available.

I'm hoping the 4.2 software update helps with the problem, but not holding my breath.

Another possibility is that I (we) just have phones with bad/marginal receivers. I have thought of eating $50 and getting a replacement from Assurion to test my luck. I think I will try that if the 4.2 update doesn't help.