The ic402 Blend is from the same Motorola line as the ic502 but is missing an external display and ruggedized housing. The ic402 does feature Java, push-to-talk, speakerphone, Java, and voice recorder.
Buying a replacement phone will not affect your existing service contract, but are generally more expensive, since they are not being discounted by your carrier.
More info...
Carrier Compatibility
Properly unlocked, this phone should be compatible with:
Nextel - Note! Always confirm compatibility before purchasing.
More info...