Buddy of mines 03 Viper ER is doing the same exact thing right now. Last year it just quit running with no warning signs, then let it sit for a while and it may or may not start. When it did start it would go for a while then quit again, so he put a new stator in. Ran fine on the next trip, and thought it was good to go until yesterday... just quit while warming it up(idling). One time while he was cranking it over with the key, I was snapping the kill switch on and off and it fired up. He also looked for a rub through under the engine with no luck today, so I think he's gonna try a new kill switch.
Just now trying to figure out if the whole throttle block has to be replaced, or if kill switch parts are available seperately.
We were real lucky this time that it quit right in the camp driveway! She fired up long enough to get it loaded on the trailer...