Vicki,
I would also suggest going to Lauerdo's profile (just search for it). This is Adam, my best friend. Get his email from there. Email him (tell him I sent you) and ask him about his system. Ironically, we both went to VoIP at the same time. This is why it would give you perspective:
1. He went with a completely different company than I did. (two solutions in one small town of Brewer, Maine. In fact, we are two miles away.
2. He used OneBox for many months and can give you the difference between each.
Remember,
While hosted VoIP isn't necessarily cheap, it replaces your existing phone system, so in essence you can pretty much break even.
One of the cool things about VoIP is you can take your phone anywhere in the world, say to a conference, plug it into an ethernet jack and your phone is basically on your phone system.
One key thing, given that VoIP uses your network (although you would want likely want to use a switch with VLAN (I shouldn't go into the technicalities now), I wouldn't do it with wireless.
