I've always been hesitant to use Pando to send files to people I don't know all that well since they have to install the Pando app before downloading my file.

So I've been relying on Send6 (Send6.com) instead. Recipients just get an e-mailed download link which is valid for seven days. Quick and painless although max file size is more limited than Pando's.

Both could be a way to harvest e-mail addresses (yours and the recipient's) I suppose so you're relying on the integrity of the companies to enforce their privacy statements.