[PaulE]

I've owned a 2003 S from new. Didn't know about the IMSB when I bought it, subesequently learned of it and at around 42,000 miles decided to proactively replace and "upgrade" the OEM unit with the LN Single Row Pro, a dual row ceramic unit that fits i place of the OEM single row unit. The LN Single Row Pro failed at 77,500 miles. I had my original engine rebuilt and went with the LN IMS Solution. The IMS Solution is a permanent replacement. A lot of the others, like the LN ceramic bearings, are supposed to be replaced periodically. If you're not doing the work yourself, or don't want to do the job more than once, I think it's cost effective to go with the IMS Solution and be done with it!