I've made a career out of analyzing machinery condition and improving reliability.
I spend just under $24k a year on oil analysis through
Herguth Laboratories, Inc. | People and Data You Can Count On!
But that's on multi-million $$ machines that run 24/7 for up to 15 years between overhauls, with oil changes on average ever 5 years (1200+ gallon reservoirs).
Overhauls can easily cost a quarter mil.
I do not do it to analyze the condition of the machine, that'd be closing the barn door after the horse got out.
I do it to analyze the condition of the oil to make sure it's not getting contaminated or broken down which could reduce it's effectiveness.
That PREVENTS metal from getting in the oil.
I have a hard time seeing the benefit of analyzing oil that gets replaced multiple times a year.
Using oil analysis to predict an IMSB is kinda like looking at the railroad tracks to see which way the train went.
By the time you have enough Fe, in the oil (that isn't trapped in the filter) to identify a failing ball bearing it's already failed to the point where there's damage to the engine.
Could you reduce the scope of that damage?
Possibly, if you were lucky enough to catch it in that narrow window of time.
You are going to have traces of iron in your oil. That is a given. You are going to have aluminium and copper and tin/lead/zinc in your oil, that's a given.
Is it coming from your oil pump?
Is it coming from the cam or chains?
Is it coming from sleeve bearings?
Is it coming from the rockers?
What is normal? What does good look like?
You just don't know without taking the engine apart.
You'd have to trend the data for a looooong time.