I was recently switched from an accu-chek nano to a Tee 2 machine and I wasn't keen on the idea at first since it was slightly larger.
The difference in price was amazing when I looked it up though... about £25 for 50 strips compared to £7 for Tee2 50 strips. So I was happier to change since I'm saving the NHS a few pennies and now I like my new machine as it needs less blood and there's less errors when testing.
I do still prefer the fastclix finger picker from my accu-check though so I've just bought some of the cassettes myself from Boots online (£4.29 for a box of 24). Much easier than putting in a new separate lancet and having to dispose of the old ones on the Tee2 finger picker. Too much faffing and they hurt more.