Ok. Thanks for your responses.
I guess I will stick to the tried and tested ones that everyone is using since I am quite new to this area.
What is the difference between the $20 Blackstone analysis and the $25 Amsoil analysis - other than the TBN ?
For $20 you can't expect super precision but both labs are OK for talking to you most about the state of your engine and secondarily the state of the oil - if you are willing to study trends and compare similar engines in similar conditions.
I think our company mechanics get the UOA's for our heavy equipment done at Ziegler Incorporated off of 94th and I35W in Bloomington (I may be wrong). I'll ask when I see the boys again. I just send mine to Blackstone.