Use the downloaded UPS rate and zone tables (choose View and not Download to get PDF-formatted rates). The rates are calculated on the demo assuming a residential address, a 0.75% fuel surcharge, a regular pickup and merchant packaging.
On occasion the UPS online rates will not agree with their published ones (i.e. the ones in the pdf's), for reasons known only to the UPS webmaster.
However, before you assume that UPS is doing something wrong, or there is something wrong inside UPSRateMonger, check to make sure you have properly installed your own zone table. This is the most common setup mistake.
If the zone table turns out to be correct and you still get errors, make sure you are using the commercial pickup rates and not the one-time pickup rates.
Finally, don't forget to update your fuel surcharge. The default is not likely to be the current rate.