Firewall throughput question

[Darryl Hoar]

Greetings,
I have had a Freebsd firewall (Older computer with (1) 3com 10Mb 
ethernet PCI card, and (1) 3 com 10/100 Mb ethernet PCI card).  
The firewall croaked on me (motherboard died).  As a quick fix, 
I plugged in a Linksys BEFSX41.

My Question is, should I build a new Freebsd firewall or just 
continue using the Linksys ? Throughput and security are my 
concern.  I can have up to 20 machines on the LAN at one time
using the internet, so traffic throughput is a factor.

Anyway, my inclination is to build a new freebsd firewall, but 
don't want to do the  work if the Linksys is good enough.

Thanks for any ideas or suggestions.

-Darryl