Well, its time to draw some conclusions.
First of all, remember that this firewall is the smallest member of SonicWall family and it is aimed at small / home office market. It is not a replacement for your 100+ PC main office LAN, but for your small < 20 client branch office. Moreover, its throughput values suggest us to use it with WANs with a (real) bandwidth between 12 Mb/sec and 20 Mb/sec at most. Considering that (at least here in Italy) most WANs are xDLS based and rarely have real bandwidth over 20 Mb/sec, this is a perfect fit for most environments.
If you need an UTM capable firewall, based on proven technology and with excellent detection rates (SonicWall is a very well-recognized brand in this market), the SonicWall TZ100 can be the ideal solution.
However forget about dirty-cheap hardware and license, because the TotalSecure 100 bundle has a list price of over 450$ (and to maintain UTM and other advanced features you had to pay over 200$ per year in licenses). The Wireless-enabled versions costs even more.
If this price falls into your budget, the TZ100 is an excellent machine with first-class features and support. The only thing that you need to remember is that you need a separate modem / router, as the TZ100 has no integrated modem.
Have a nice day!