Best device for use with OpenWRT/DD-WRT/etc?

[H. Kurth Bemis]

Greetings to the list - 

First, a little background;  I'm evaluating the replacement of several
point-to-point and frame ports and replacing the frame port in each
location with Business grade broadband (DSL and cable), and using
OpenVPN to connect each remote location back to company headquarters.
The offices are generally located within range of Verizon DSL G4
Communications DSL or Comcast cable.

Each location currently has several Cisco devices, an edge router, VPN
concentrator, and PIX.  I'm looking to replace these devices with a
single Linux-based device running OpenWRT, or a derived project, at each
location, utilizing OpenVPN and iptables.

I have plenty of experience with OpenWRT and DD-WRT, unfortunately the
only hardware I have worked with in depth is the Linksys WRT54GL, and
having worked with Linksys gear of all types, I'm not sure I would tote
them as a replacement for a Cisco router.  My primary concern here is
reliability of hardware, not software.

Can anyone recommend a system, preferably small in size, as a
replacement for a Cisco router or firewall?  It should run OpenWRT, or a
derived work.

So far I've been looking at the Asus WL-500G, but I'm always open to
suggestions.

Thanks
~kurth