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I agree with most of your summary, thom4782.
My primary issue with "The IMS solution" is that replacing the ball bearing with a plain bearing may have unintended side-effects. The bearing type has an impact on the system. For example, a plain bearing is less efficient, which means that there is consistently more load on cam chains and the IMS teeth. I don't claim to fully understand the physics but I do know that unnecessary changes are a bad idea by definition.
In cases where the stock bearing is properly lubricated it has been shown to last over 200k miles with no significant wear. Since the chances of failure in a pressure-lubricated ball bearing setup go down to virtually nil, the risk of causing other problems by changing the bearing design suddenly outweighs the possible benefits.
Idling a car for a long time is an interesting but it is not a true test of the known-failure conditions. For example, it is known that unlubricated startup is one of the most stressful times for a bearing (and double that concern for a plain bearing). There is no reason to believe that temperature was a significant precipitating factor in the bearing failure. In the very worst cases, it took at least 30k miles of varied driving and multiple starts for the bearing to fail.
I suspect that we will find out what the new failure modes of "The IMS Solution" are in a few years when the first ones start to fail.
If you want peace of mind, choose a solution that is extremely reliable (oil-fed bearing) over one that is more likely to fail ("The IMS Solution"). In the absolute best possible failure scenario for "The IMS Solution", it is still thousands of dollars to repair. In the worst, it's still replace the engine time.
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