We are a VoIP Telephony Provider here in UK and I want you to know that VoIP reliability is determined by your provider's fail safe measures.
As we are a subsidiary of AstraQom International (a global VoIP provider) we have several data centres around the world (e.g. UK, Canada, US, New Zealand, Australia etc.) and in the event that the London data centre goes down phones automatically register with the next closest server and this takes up to 25 seconds.
On the other hand if your internet goes down, we have in place an Internet Failover or Emergency Redirect feature that automatically forwards calls to a different number (e.g. mobile) when our system detects that your devices are no longer registering.
We can help you with everything you need and even provide a 30-Day Free Trial so you can test the system.
If you company commits to a 2 years contract you can choose to either get a 35% discount on monthly recurring charges or to get a free HD IP Phone with each user that you get.
Regarding having a dedicated internet connection, that is always good but keep in mind that 1 active conversation requires around 128 Kbps so even if all your employees talk at the same time (8 active calls) you are looking at 1 Mbps requirement. If your office does not heavy internet traffic (e.g. downloads) a 24 Mbps connection should be fine.
I advise you to check your internet connection for packet loss and jitter before taking any VoIP service and you can do that at the link below:
(it requires you to have Java installed on your machine)
We include IVR Professional Recordings that can go anywhere from £30 to £500 depending on the number of words that you have and we also include E-Fax Numbers, Free Portability, anywhere from 500 to Unlimited Landline calling and 100 to 600 mobile minutes PER USER not per account.
Getting your own IP PBX makes sense maybe when you have 70+ users but otherwise the costs involved are not justified.
I encourage you to take a look at our plans http://astraqom.co.uk/business-voip/hosted-voip-pbx/
and see for yourself what we offer.
If you need a custom package we can also arrange that but I believe our packages are built for every time of company.
For more details you can send me a PM or call our guys at 0800-048-8003 and what the best solution would be for your business.