I'm at 100K with my '01S. My IMSB shows no sign that its near the ends of its working life. My clutch has seen a lot of miles, but isn't slipping yet or making noises. While I don't what to spend the $2,200 US to replace these parts, I plan to do so in the next few months for two reasons.
First, I plan to keep the car for another 10 years so longevity is important to me. Second, and most important, I've owned my car for 10 years. I know how it's been maintained and what has been repaired. So I'd prefer to stay with a car I know intimately than either spend a lot of time looking for a well documented alternative or go with an unknown.
So that's my risk calculus. I'm willing to spend the $800 US extra to install the LN bearing when replacing the clutch because that's a small price to pay when amortized over 5 to 10 years or when avoiding buying an older car with a unknown history. And that's really the heart of my risk profile.
BTW: if you visit the following site, you'll see some data on LN bearing failures: dual row = 0% and single row = 0.1%.
IMS 101 | IMS Retrofit. See third paragraph from the bottom.