Does anyone have experience with SMS marketing websites?

[Brian Filmore]

I'm comparing several websites to market via SMS (text messages), and am wondering if anyone has any input (either positive of negative) on the effectiveness of this technology as it relates to RE.

Originally I was using a list of cell phone numbers purchased from http://www.cell-phone-list.net in conjunction with a predictive dialer to reach potential customers for a RE related project I'm involved with. I've since built a fairly good size opted in client database and am now leaning towards using text messages to further reach everyone who opted in. 

I'm considering Trumpia (http://www.trumpia.com) but any input would be appreciated. Thanks.