Since your Part 121 operations are outside the U.S. most of the time, do your agust FAA inspectors and handlers test you on knowing when an airport is 2.3 for cicling and when it's 5+ ("+" is because PANS-OPS, unlike TERPs, wisely increase the limit with airport elevation).
We don't operate to 14CFR121 regulations, as our aircraft are not US registered.
However, many of our pilots are FAA rated, and certainly know the difference between Terps and PansOps. If they did not, they wouldn't be here...
Personally, we find no special difficulty with circling using Terps procedures, because...that is how we conduct our training....IE: we do not now allow our pilots to maneuver outside the 2 mile visibility area during circling, unless the weather is VMC.