Good evening
I am partial to the LBT... have for a while & I do not have a Crabtree. Have tried the others and they are no help to me ...
But with a little trial and error I would have to say IF you do not have the now $100 for a new LBT the "hammer& Ball bearing SMACK" works as good as I will ever need. A good dial caliper is also VERY helpful in measuring the impresions in the Pure lead sample and the "Unknown sample"along with a calculator. BUT you cannot test individuals Boolits with the Ball Bearing Test so the LBT still gets out of the box off and on.