In the article on the cordless SIP phone you mention your use of OnSIP and I was wondering if you could comment on your experience with that service. It seems pretty awesome from a small biz perspective but just wondering if you've run into any issues in actual use.
I selected OnSIP for my employer about 15 months ago and they have been excellent. We were in the beta program of the OnSIP management portal before it launched.
We have around 20 extensions at 8 locations around the US. All on various forms of connectivity. All of our DID at our UK head office are mapped to extensions within OnSIP. Thus all of our 3/4 digit in-house dialing at head office is identical out if the field offices.
For small businesses I think that they are great. The deal clincher for us was lack of per-phone monthly costs. Just pay for usage. Period.
Personally, I really like using SIP URIs where possible and completely bypassing the PSTN. Now that we have some Polycom IP650/550s in the company, and Siemens S685IPs we're using G.722/HD Voice where possible and the call quality is simply outstanding.