I just switched from Big Red to Sprint two months ago. I had been with Verizon for almost 10 years and always liked them. The only problem was that I wanted a better rate and Sprint was too good to not try. I live in NC, my parents in MI (they were on Verizon as well), and I asked them to join me on Sprint. We bundled the everything data family with 4 phones and now pay about the same for unlimited data, messaging, plenty of voice, etc. for the same price as we paid for just voice on Verizon. Granted, having my parents jump on with us provided even more savings, but so far I am pretty happy.
I pretty much never dropped calls with Verizon (once in a blue moon), with the exception of a dead spot just before our exit on the freeway, so I was very happy with Verizon's coverage. So far I haven't dropped a call on Sprint in two months, and coverage seems great so far. I have dealt with customer service in returning my original phone under the 30-day policy, I returned a Pixi and got my Hero... it was very easy and I had no trouble. No restocking fee or any hidden fees, just had to pay the difference in phone costs from free Pixi to $80 Hero. My parents also ended up exchanging the Pixis for Pres... and my wife kept her Pixi. We have all been very happy with Sprint two months in, and paying the same price for unlimited data, messaging, sprint nav, etc., and having the same number of voice minutes is pretty sweet. It's also nice that sprint is unlimited any mobile to any mobile since almost everyone I talk to is on a mobile, we don't use anywhere near as many minutes as we did with verizon since they are only unlimited in network.
That's my experience so far... any other questions, let me know.