Which SMS Hardware to use?

I’m planning on buying an SMS terminal to use with Nagios` “SMS Server Tools” for notifications via SMS. Who has got any expierence in this? I’m interested in good as well as bad expierences.

I do not want to use any form of mail-to-sms gateway, because that would compromize the monitoring of my mail server (you wouldn’t get an SMS if your mail system is out of order).

I’m currently leaning towards the Falcom Twist. Mostly because it seems like a simple device and I know its price ($250)… (See: http://people.su.se/~leifj/doc/html/gsmmodem.html )