I think the thing to consider here is weight loss (lbs). Yes, the doctors scale will be a lot more accurate as it's an expensive scale that can be fine tuned. The ones available at the local Walmart are between $10 and $40 dollars. They're not built the same, obviously much cheaper and most likely less accurate... BUT... they do the same job. If you lose 10 lbs, you lose 10 lbs. Whether it's on the doc's scale or your own.

Do yourself a big favor. Don't check your weight more than 2x per week. You're weight fluctuates so often, you might get discouraged if you're checking it too often. And use a tape measure. Sometimes you can lose inches vs lbs. Just read some of the posts around here.

Good luck!