Although we have other options (ACH, Wire, PayPal) but we also want to make payouts to our customers securely, but we're not sure what the ramifications will be.
I mean, what if:
.. are some of the things that come to mind.
We're looking to send out checks mainly because it would cost a lot less than international wire ($25 or more), but only if its without additional hassles.
You also have to consider if the recipients (such as affilate marketers?) actually want to receive US checks.
In most other countries, checks are nearly dead, domestic bank transfers (like ACH) are the way to go. Having to handle a paper check from the US is, for most countries, really archaic and a real pain. With the possible exception of Canada, it nearly always costs the recipient a lot ($15-50) to deposit a US check, and it can take many weeks (or even months) to clear.
You're better off offering ACH domestically and Paypal to everybody. Most overseas people will prefer Paypal (be sure to use bulk payments so they don't pay to receive it).
You could also offer international wires as an option, either by charging the overseas person all or part of the cost (most will willingly pay it to avoid having to mess with paper checks!), or (more friendly) just have a much higher payout minimum for wires ($500 etc), and eat the wire cost for that small minority of cases.