On the price comparison alone, then yes, I would.
Because don't forget you are currently paying �19.99 p/m to UKSUN, and
also �11 p/m (ish) to BT for the landline rental.
That's pretty much the same price as the �31.95 you'd pay to Virgin for the complete package
But you'd also be getting the extra TV service, and of course the 20Mb speeds