KIVA doesn't pay returns to lenders for its loans. That isn't a criticism, just a statement of fact. It took me a while of reading to understand how their business compares with bonds. The advantage of Kiva is that you get to see who the borrowers are, and what they'll use the money for and that 'intimacy' can certainly provide emotional impact.
I thought I'd have a look at other similar business models and see if anything else was going on in the microfinancing world. I found
Micro Place. The first issue I had with it was that it is an eBay company - but I looked past that and investigated. Instead of giving money to the borrower via field agents, you give money to the micro-financing companies (via securities) who can then loan that money. Example:
Oikocredit:
Borrower repayment rate: 100% Woman borrowers: 100%
Total loan portfolio: $2,415,740 First-time business owners: - -
Number of active borrowers: 12,662 Operational self-sufficiency: 127%
Avg. loan balance / borrower: $259
You get a small interest, in this case it is 1.5%
It is an exercise for the reader as to which method they prefer, and I've no idea if one can be said to be 'better'.