You should be able to get a Vigin+ box installed for �75 and retain your existing services - we did and would now hate to be without it. You wouldn't need any other recorder unless you wanted to transfer recordings onto a DVD or something (including another hard-disc recorder), The Wharfedale has a much bigger memory - the V+ is "only" 80Gb - but we've never filled ours.
I love my V+ box - I've just looked at the Virgin site and it is �99 now.
I don't know if you'd have to pay extra each month - it depends on your tv package and what sort of deal you negotiate.
However, it is by far the easiest way to watch and record tv - three tuners (one more than Sky+) so you can record two and watch a third channel at the same time; pause and rewind live tv too.
A Freeview digital recorder is excellent for recording your freeview channels, but if you want to record your Virgin channels it's a lot of flaffing - you have to set it to manually record the AV or EXT channel your Virgin box uses, make sure your Virgin box is switched on and most importantly set to the channel you want to record and don't change channel during the recording.
Give Virgin a call and see what they can offer you. I also have a cheap (�20) dvd recorder that records on to dvd disk - I can download programmes I want to keep from my V+ box to dvd very easily indeed.
I have just bought a Sony DVR-HXD870, Only had it a couple of days, so I`m still getting used to it. It is amazing, so many features. Freeview, a usb port, so you can play direct from a pen drive etc. pict bridge slot, plays divx, avi files.
I am on Virgin and can record either from Virgin, freeview or terrestial tv. Not sure yet if I can record two programmes at once.
Thats what I want to hear as after contacting Virgin we would have to either pay �99 for V+ then �5 a month, or pay �150 and not pay �5 a month. We've decided to go for the recorder box.