1st and second had flaws but the third works well and seems accurate compared to a stand-on weight scale. I like the manual spring rather than digital and button batteries; that can be hard to find, reload, or fail at any time before or during a trip. The first unit problem was the active weight dial did not zero and was a few pounds off, on the wrong side of safe (not good), second unit the reset pin was too tight and the would return to "0" with the active needle and the active needle would push past it sometimes. The third one works fine. Great Amazon policy on fast replacement of defects with 'Prime'. The reviews stated a few flaws are likely so I figured I might get lucky; third time was the charm! Not a great/consistant quality built-item but this one works right.  'Magellan's' has the same unit, but higher priced and you would pay shipping both ways. Amazon is great about standing by THEIR products and simple online returns with free local pick-up. This also has a tape measure. It is very lightweight and compact/foldable/packable.

Update 5/7/14:

Still works great and we use it often. We often let others borrow it at the airport. The airlines see my luggage as a pound or two lighter than it reads which is great and on the safe side, kind of like a speedometer that reads 70 but you are really traveling at 68-69. I am sure these have even gotten better.

I recommend this, would buy again, and I hope this helps someone.