I'm using at my home for three months and have no complaints at all ( i'm running 3.0(24) right now ).
I use my SmallOffice as DHCP server for my PC's, two fixed and a Laptop with WiFi and a PDA with Wifi and of course as a ordinary pbx with two 4602's & one BRI.
I use WiFi for internet access (sDSL) and H.323 calls with my PDA and PhoneManager IP on my Laptop, really super. You do not need a third party router for it.
I even had a IPSec tunnel with a collegue who has more or less the same config.