Well, I have a pre-paid/pay-as-you-go Passport SIM, just a global roaming SIM with a UK number. I already know my Verizon phone can send to it, but the info with the SIM specifically states it cannot respond/send to CDMA carriers. Lame.

I'll be picking up a SIM in Ireland in about a month (probably Meteor, they seem to have the best pay-as-you-go option for my needs) and I'll find out how well Meteor works with texting home to Verizon Wireless and T-Mobile USA.