I had Sprint for years, and absolutly loved the service, the rates and the Sanyo phones which own. I switched to Verizon because my GF is with them and I wanted free mobile to mobile and text messaging.
Verizon is expensive, I pay way more and get less. Only benefit is the rare times I have to call customer service, I wait no longer then 1 minute tops, usually it's instant. Now the quality of CS sucks as much as Sprint, but with Sprint I was on hold for a long time, always.
Sprint has better phones, Verizon is playing catch up, and if you like style without substance (IE Motorola) they are on top now. Sprint has Sanyo, the newer Sanyo's don't match up to the 5300's, but are still far better then most phones.
Sprint for me = $40 bucks = 1000 minutes, good coverage, I added 5 bucks for mobile to mobile. Also they have nights and weekends, with nights starting as eairly as 6! for only a few bucks more a month
Verizon = 80 bucks for 1350 minutes + $10 for unlimited text messaging and IN calling + $35 for unlimited data on my Motorola Q. Which ironically isn't "unlimited" but capped at 10 gigs a month, and if I teather from my PC I run the risk of getting my account sh*t canned. 10 gigs on a mobile sounds like a lot, but the speed is pretty good 50-60k and I racked up 150 megs in 2 days with fairly light usage. I'd imagine if I started to stream radio or watch streaming video 10 gigs could be hit way before 30 days. I dunno what they do if you go above 10 gigs. Knowing Verizon, probably make you pay out the a$$. Also, Verizon cripples the hell out of their Bluetooth phones. I mean I have a Smartphone and I can't xfer files from my PC to it using Bluetooth (which sucks) and on the other phones, you really have to rig them to get them to do what they should if Verizon wasn't so damn greedy.