I suppose that all depends, do you want to find the one in worst condition, or the one in the best condition?
Most Engine makers suggest thay you open up one or two mains at random, to check the condition, and if they are OK no need to open up the rest, If they are in poor condition then you have to open up all the bearings to check / renew them.
If the engine is misaligned, there will be a lot more force on the drive end main bearing and that will become more worn than the rest, the overhanging mass of the flywheel can also cause more wear in the lower bearing supporting it. The "bend" in the shaft caused by the weight of the flywheel or misalignement can also cause excess wear on the opposite face of the next bearing.
If the chocking or supporting structure for the engine has failed causing excessive crankshaft deflections, the deflections may also indicate which bearings are likely to become damaged.
The tension on a chain drive for a camshaft, (remember them?) can also put more load on the adjacent bearings and cause them to wear more.
Some engine makers may advise you, either in Service Bulletins, or if you email the Technical Department, if any particular bearing number is prone to problems.
Some makers specify that the bearings should not be refitted if they have done more than a certain No of hours because they say the bearing will no longer conform to the journal after it has been disturbed. I sailed with Bergens, the mains were supposed to be good for I think 24,0000 hours but if you opened a bearing after about half that you had to scrap it.
I hope you get a few more comments, and let us know who won the beer!!
It is always better to ask a stupid question than to do a stupid thing.