The main factors you want to think about when looking for jack stands (in any price range) are the construction and the engineering. Due to physics — fulcrums, tipping points, etc. — the size of a jack stand’s base and the height you use the stand at are both very important when it comes to stability. The higher the jack stand holds the vehicle, the less effective the base will be at keeping the stand from tipping under pressure or sudden movements. Hence why it’s better to have a wider base as well.
You should also look for jack stands with a flatter base (as opposed to one that sits on the edge of its own frame) if you expect to ever use it on asphalt. Warm asphalt tends to be softer than cold, and the narrower the point all that vehicle weight is being pushed onto, the more likely the jack stand feet are to start sinking in. Which, in turn, can make stands uneven and far less stable.
Weight limits are also a big deal, but you don’t have to worry too much about a low-cost stand not living up to its advertised potential. Barring something like a factory defect, if a pair of stands claim they can hold up to 3,000 pounds, they should be good for up to 3,000 pounds. Just be sure you know how much weight they’ll be working with beforehand.
