Quick update:

Loan of 3 BTC was given for a week, and 1 BTC interest paid on time.

Loan was extended for a week, and 1 BTC interest was paid on time.

Loan was extended for a month. Did not want to pay when payment was due because value of BTC had gone up, but promised to pay within 10 days. Over 10 days have passed with no communication.

No need for "I told you so" posts, but if anyone has anything useful to contribute, feel free.