PANiCnz:
My main concern is that with a 100/20+ connection you start getting into a situation where you actually need some semi decent hardware to route at line speed. Said hardware is often more expensive than the ~$200 an ERL costs, consumes more power and generates more heat.
pfSense is a great product, but if starting from scratch (i.e. no spare PC hardware) then on cost alone I think its hard to beat the ERL or similarly spec'd MikroTik kit.
Even more so if you want to run encrypted OpenVPN traffic (AES-NI). Speaking of Mikotik, I was considering RouterOS except they have a curious implementation of openVPN i.e. no UDP support, which I required.
Agreed on the heat/cost/power equation, and it's probably overkill unless you do need the specific features and yet.....[echoes of Tim the Toolman Taylor....]