Security capabilities: 

Most vendors use signature-based technology to provide gateway anti-virus protection. However, the time lag between attacks and the availability of the corresponding signature files (used to identify the threats) can be up to a few weeks in extreme cases and create a window of network vulnerability. Real-time UTM is therefore recommended as a more reliable option.

Performance:

UTMs handle multiple security applications simultaneously.  This can lead to significant processing load, depending on levels of network traffic. This issue is minimized by intelligent UTM software design, enabling ‘good’ traffic to pass through without being subjected to the full range of scrutiny.

Single point of failure:

Since all of the security functions are combined into a single device, should this appliance fail, all the functions become instantly unavailable. Running UTM appliances in high availability configurations minimizes this risk.

Fortinet:

FortiGate systems integrate the industry’s broadest suite of security protections – including firewall, VPN, antivirus, intrusion prevention (IPS), web filtering, anti-spam, anti-spyware, and traffic shaping – that can be deployed individually or combined for a comprehensive UTM solution.

Check Point Software Technologies:

VPN-1 UTM from Check Point combines proven security into a solution that boasts centralized management, enhanced update-ability, and advanced reporting. They offer a complete set of security features including firewall, intrusion prevention, antivirus, anti-spyware, web application firewall, VoIP security, instant messaging (IM) and peer-to-peer (P2P) blocking, web filtering, as well as site-to-site and remote access connectivity.