I had a lot of wasted tests for the first couple of cartridges, but I've got the hang of it now and don't get any miss-tests.
I make sure the blood blob is big enough before I open the test strip cover, and then move the blood slowly to the test strip until it is just touching and the strip draws the blood up. Don't push your finger against the strip. Pull your finger away as soon as you hear the bleep and get the 'Test in Progress' notice.
I can't compare the accuracy as I have only used the Accu Chek Mobile so far, but all meters are likely to have different readings.