VK Mobile Kickflip
would this be true with any cdma phone?...
so if i got a verizon phone.. unlocked it.. could i use it on a sprint network?..
No. Verizon phones are generally unlocked, but Sprint won't activate a non-Sprint phone. Their activation system is tied to an automated database of all Sprint phone ESNs, which lets them enforce this quite effectively.
...especially with their evdo power vision network?.
No, especially NOT with Power Vision. Even if there were some way to activate a Verizon phone on Sprint, only basic voice service would work. All of the advanced features like Power Vision use different, incompatible connection methods and/or technologies.