How important are revisions to part numbers?

[Sharkie]

For the collective brains trust on here

I have a friend's car that has a "broken" coilpack.

Part number is 04E905110L.

Latest revision is 04E905110P which costs ~$150 each

What is the risk in running a version that is not "current"?

To make this question more interesting, I have in my spares crate a full set of 04E905110B, all in perfect working condition, and they are FREE. Can I use those without any real issues?

[kamold]

Part number suffixes can mean anything from a change in manufacturer, a revision to an existing part, to a totally incompatible part.
You need to check in the ETKA parts catalogue for the car in question to see if the part has a supersession part number.
If you want to shoot me the VIN privately I can check for you.

If the B part is compatible there isn't any reason why you can't use it.