WD My World Edition NAS as a VPN server?

There is apparently a hack to install the OpenVPN server component on
WD's 'My world edition' linux based NAS thingy.

http://mybookworld.wikidot.com/openvpn

Anyone done this, and feel comfortable about the security of this
solution? Private IP thoughput issues? I can serve 1.3Mbps out of my
local network, the intention is to stream standard definition video
through the tunnel.

Finger hovering on the Amazon 'Buy' button at present, 1TB for £99

Or should I get an Atom based PC, one of the Acer Revo Linux things -
and hang a large SATA drive out of the back. £189.99 currently + cost of
a large 3.5" drive.

Trying to limit my electricity bill for things running 24/7.

--
Adrian C