Good things to think about. Thanks everyone! I anticipate a minimum of 60 minutes of talk time I'll need while I'm there. My quick number crunching shows that Verizon Wireless will charge me $2.89 per minute to "roam" in Belize, or $173.40. Telestial says that the cost to call the U.S. on a Digicel card is .86/minute. That's $51.60, plus the $55 they're going to charge me for the card, minus the $10 credit. That's $96.60. A potential savings of $76.80 by getting a Digicel card. But on the flip side, $76.80 might be a reasonable price to pay to avoid having to track down a Digicel card, register, buy the additional airtime vouchers, etc. And if I somehow don't use as much time as I anticipate, I'd wind up with a Digicell card and additional airtime that's basically money wasted.
Sorry, it's a Monday afternoon and I'm feeling overly analytical. :-)