I've never used Trail Boss, but have used the Li'l Dandy for years with various powders. Always check your weights with a good powder scale and it's very common to find a variance from the RCBS chart and actual wt. Probably never enough to worry about safety but you will find wt. can be different than their charts. However, if you're consistent with the way you throw the charge both the Li'l Dandy or Uniflow with small cylinder is very precise. Still, I usually check after 10-20 charges from the loading block visually and occasionally weigh but RCBS is as good as they come.