Thanks. Yes it is very difficult with the biases from sales people. You could probably get by with 380 up, but that would be the bare minimum, and you would need it all the time. With two on the phone at the same time, you couldn't have anyone uploading something taking up bandwidth. The hosted versions and the non-hosted PBX systems have QOS or quality of service which helps with that.
What I would recommend is Googling hosted VoIP in your area and trying to talk with one. They can explain it to you much easier. You could ask them about the one you are talking about. Of course, my guess is they will say horrible things about it, but if they don't, then you may be OK.
The independent salesperson who got me interested in VoIP probably had to answer somewhere in the neighborhood of over 100 questions. VoIP, especially commercial, is SOOOO different than regular POTS. Plain Old Telephone Service. I would love to do hosted VoIP. It is simply awesome. The two companies I talked with for references had around 1,000 phones. That is $40,000 per month just for the leases on the seats. (Phones). But, that is another great place for VoIP. You can have multiple offices with the same phone lines.
