I am a factory representative in the tire service equipment business, with 26 years experience, so perhaps I could comment on this.
The whole point in using a balancer is to get an accurate, repeatable reading on the imbalance in your tire/rim combination. One that you can count on to fix the vibration problem.
The problem with low-cost offshore balancers is, the machines are not made to the same standards and tolerance levels as the US or European machines. They are built strictly to a price.
Believe me, if a tire store chain with 1000 locations can find an accurate, reliable balancer and save lots of $$, they would do it. But, look in any major tire shop, they usually have Coats, Hunter, Corghi, CEMB, Bosch, or another reputable brand.
The readings you get from the cheap machines are suspect. You cannot rely on them. If you can't trust the readings, what good is the machine?
Like with the cars we all love, if your finances don't allow the purchase of a professional machine, it is better to find a nice used "low mileage" name brand balancer, than buy a new, cheap product, which will break in short order.
I visit shops all the time that made the mistake of ordering a cheap machine to save $, and want to dump the machine 30 days later, because it has broke, or can't hold its calibration, and they can't get parts or support.
Or, find a local shop which has invested to buy and maintain the right equipment, and pay to have them balance your tires.
By the way, my line is at Home. CEMB (pronounced "chem") is the world's largest balancer manufacturer. I am their Virginia rep.