Sometimes (for smaller offices or companies), an Alix or Soekris can be used instead of a more expensive product from Cisco.
VPN
On an Alix 2D3 with glxsb crypto accelerator enabled you get +- 20 Mbps IPSec VPN throughput (with AES-128 CBC)
3DES speed is slower, but this can be enhanced with a miniPCI hi/fn card (more then 30Mbps)
Cisco mentions 100Mbps (max!) for its ASA5505 appliance. This device also uses a Geode LX processor, but it comes with
other accelerators to enhance aes/3des speed.
High-Availability
PfSense is clearly a winner if you need HA for a low price. The Cisco ASA5505 (Basic) has no HA support.
HA shouldn’t be expensive. For example you can use Multi-WAN features with an ADSL and Cable subscription.
2 ALIX PfSense boxes and you’re done.
Price

Cisco ASA5505 SSL25-K8: Firewall. DMZ. VPN (25 SSL users). max 20 VLAN’s : more then 2200 euro
Alix 2D with PfSense: Firewall, DMZ, VPN, VLAN, CARP Redundancy : max 150 euro
Off coure, I’ve you invested a lot in Cisco hardware and training, you can better use Cisco devices.