For what its worth, Excellence magazine's
Porsche Buyers Guide, (published in 2012) says the following about the Boxster IMS bearing issue:
"For the best chance of avoiding the common engine problems, which can affect any 986, look for Boxsters with at least 50,000 miles. RMS and IMS bearing problems usually (but not always) happen sooner if they are going to happen." (pg 26)
There seems to be a lot of disagreement on the IMS bearing issue, even among experts. I am just posting Excellence magazine's printed statement on the issue, not my own opinion. As I said, take it for what it might be worth.