I've got the same dilemma. VM's support forum is worrying to say the least, although i do realise only problems will be posted there. Things that concern me are iplayer not working, picture quality and things generally being more complicated to do and, if i'm unlucky with the box/signal/tech, being without a Tv service over xmas. It does seem to be a tempremental thing. There is also the issue of red button/reminders but I don't use them anyway.
My head says its probably wise to wait a few months but since when did i listen to my head

Why don't you go first and let me know how you get on