i have used them in the past, and sometimes messages can take a good few hours to actually reach the destination phone, and one or two messages dont get there at all. So, unless you havent got any available credit on your phone, use that instead.
I just prefer to send phone messages by phone and e-mail by computer....just a personal preference i suppose.
Cheers psd anyway, for alerting us to another bargain. And hey, it is free!!!!!