I have a Park Tool one, and I noticed that a local coop's scale (same model) was a little optimistic in its weighing. Great for feeling good about a big bike weighing less than what I hoped, but ultimately not accurate. My PT unit has many fewer weighings on it, but curiously, it gives two different weights when you toggle between Bald Eagle Units and Metric (if you calculate the conversions). I go for the lower number.

A friend [MENTION=340794]Dfrost[/MENTION] gave me a tiny hang scale years ago and I've used it to corroborate other scales' readings as it has matched them well, so now it can do so for my PT scale. This sounds like a bad response: "Why doncha just buy another hang scale and see how it does?"

How long have you had this scale? What brand and model?