>
> (a) I work at home and have 2 MB cable internet.
That's a good start

> (b) It is on for about two-thirds of the working day.
That's not so good. Why isn't it available 24/7?

> (c) 90% of my calls are to 01/02 and 0845/0844/0870 numbers.
But what is the ratio of 01/02 to 0845/0844/0870? Non-geographic numbers are
bad news however you make your calls.

> (d) I recently an NTL deal for 24x7 free calls to 01/02 landlines.
OK

> (e) I pay £20-£25 per month just for calls (via 2p-a-min Tiscali).

I don't think I understand that.
>
> ---
>
> (1) Is there any cost advantage in me getting VOIP. I think that in
> my situation I would have to pay to use VOIP, wouldn't I.
No, at least not in the sense I think you mean.
You just buy the hardware, probably an ATA, and sign up for
one or more voip accounts. It' usually free to sign up and with
some like Sipgate.co.uk you can choose an incoming number
in almost any UK STD area. All free.
To make outgoing calls you put credit into the account. Sipgate
charge per minute for 01/02 calls, you might prefer an outgoing
provider like voipcheap.com (the one I use) which has a slightly
different credit protocol.

> (2) What destinations would I be better off using VOIP rather than
> NTLs 24x7 service?

Arn't you paying a premium in standing charge/line rental for this
privalage?

If you are calling international destinations that will be an important
factor in choosing your voip provider. As you will discover there are
many of these, largely unknown names to the public at large,
many are owned by the same corporation! But the main difference
between them is the rates they charge to particular countries.

>
> (3) As it just so happens I need to get a DECT handset. Is it worth
> getting a DECT handset with VOIP capability (eg single Panasonic
> handset £100 KX-TG9150ES verus non-VOIP £48 KXTG7120ES) or is the
> steep extra £50 for VOIP mainly for convenience rather than for
> economy?

I would recommend you go for an ATA and an ordinary DECT phone.


>
> Thank you for any info.