What's a better measure you can do on your own?
I've gone through several cycles where I have gained and then lost weight. Right now I am in another weight-loss cycle as a result of a overly sedentary lifestyle; this is the hardest "comeback" that I have ever staged.
When People ask me what my goals are I always tell them that I want to loose 30lbs. I don't elaborate any further unless they show a real interest in what I'm doing.
In all actuality, my real goal is to loose an "aparent 30lbs." Essentially, when I have reached my initial fitness goals I want to physically appear as if I were 30lbs lighter. Since my regimen is a combination of diet, aerobic exercise, and weight training the actual metrics at the end of my goal will most likely result in me having lost some weight, but also having gained some weight as muscle mass; this is, in my opinion the healthiest way to approach weight loss.
Having said that, normal metrics such as BMI, and weight are not good indicators of improvement. Its actually better, at least for me, to use much simpler criteria. In my case I look at easily measurable things: Am I getting stronger? Is my cardiovascular training getting longer and/or harder? Am I sleeping better at night? How are my sustained energy levels throughout the day? Am I staying fully hydrated? Am I handling stress better? Is my overall attitude positive? And finally, do I see visual improvement by taking a self-photo every 2 weeks?
Really I only check things like weight and body fat % at the end of a particular fitness goal and even then I don't give it much credence.
Most people don't just need to "lose weight," they need to improve their overall fitness. If you're overweight, then increasing your fitness will include losing weight, but it's not everything. And the best measure of your physical fitness are simple physical exercises.
There are some home scales that do electrical impedance testing but they are inaccurate too.
I think that the BMI calculation that is done at home is bad for people trying to get in shape. They worry too much about the BMI and not about the important stuff such as building muscle which will help you keep the fat off in the long run.
In fact, wait circumference is pretty important, especially for me. Central Obesity (i.e. the stomach, love handles, etc) is correlated with a lot of health problems - much stronger correlation that just being overweight in general.
Other than that, the pinch test works well too.