[GadgetKen]

OK, understood, the callback restriction would just apply to callbacks on Bermudian landlines, not a callback sim.
Digicel Bermuda is currently doing a promotion with free incoming on both prepaid flex (my account) and postpaid accounts...but the catch is that is only for calls from other Digicel callers.
Calling will mostly be one or two calls home each day plus maybe a local call or two, so will just use the balance on my Digicel card as-is on my Razr.
Do have Skype installed on the Tilt so that would be a cheap call if I'm near free wi-fi that doesn't block VOIP; but tend to use that phone just for US prepaid data (email, light web browsing, occasional light tethering) and installed software. Might try to access personal email via wifi or a Digicel or Maxroam data connection as an experiment.