When comparing are you using the Connected GPS?
If not first we need to compare ateps and figure out if either is correct. Go for a walk, count the steps you take then compare.
For my Blaze it seems to be 20-30 off, whether i count off 100 or count off 1000, it seems to be always 20-30 off. A walk of 100 steps this is not good, but a walk off 1000 steps this is exelant.
Your experience mau vary.