Just had a long call from a Mr. Crolla at VM:
If I forgo the 3 tickles (which were not that much of an advantage to me) I get a free installation next week of a 1Tb Tivo, the HD box moved, also for free, to the lad's bedroom, and an overall monthly saving of £7.75.
Plus they have left a refund of 1 month's landline cost on my account, and Talk 08 add-on remains free for a year !
Thankyou VM!