USPS Fingerprints for FBI

Has anyone ever visited USPS for taking fingerpring for FBI PCC required for Canada / Australia immigration? i read this on FBI website

Step 1: Go to https://www.edo.cjis.gov.

Step 2: Follow the steps under the “Obtaining Your Identity History Summary” section. If you submit a request electronically directly to the FBI, you may visit a participating U.S. Post Office location to submit your fingerprints electronically as part of your request. You may go to any of the participating U.S. Post Office locations nationwide upon completion of your request. Additional fees may apply.

If you choose to use a U.S. Post Office location, you must complete your application and payment electronically prior to visiting a U.S. Post Office location to submit your fingerprints electronically as part of your request.

If you choose not to use a U.S. Post Office location to submit your fingerprints electronically, then you may still mail your completed fingerprint card, along with your confirmation email received when you started your electronic request, to the address listed on your confirmation email. The request will continue to be processed as an electronic submission once the completed fingerprint card is received.

What is your concern with submitting the fingerprints at the USPS location?

This is electronic fingerprinting offered by USPS, not the traditional one we do with ink on paper.

Can person on a Visa do this safely? I am looking for some1 who has got this done recently.