A few weeks back there was a discussion on how the different meters registered differently.
We did an experiment with my family. We took a blood sample and tested it with both the Aviva and the Freestyle lite.
These are the results:
FreeStyle Lite Accu-chek Aviva
95 106 (We used two different blood pokes)
The only big difference we saw was when DH had two blood pokes and I took one measurement from one blood poke and another from the other. Otherwise they were pretty close :-).