Engine component scale recommendaton

I'm in the market for a good quality scale for weighing smaller components, specifically engine parts. I stumbled across this website and I'm not sure which style/model I should get. Also what resolution is practical? Any recommendations?

Lab scales: http://www.scales-co.com/cart.php?ta...category_id=60

Triple-beam scale: http://www.scales-co.com/cart.php?ta...category_id=95

I have used a lab scale, and a simple kitchen food scale. Both worked just fine. However make sure you don't exceed the scale capability, as it will typically offset data following that, it will zero again, but weights will be slightly off.