I have the mold and hand pour the belly section as well as cut off the tail sections to re-inject the body portion. Very easy on either account. With the body section just a hair larger than a 1.75 inch small fry, its easy to play with colors. You can make some outstanding baits in this mold.
I'll note here, that if you are doing the tail trim to make the body a different color, leave the tail color shoot in the mold and trim while in it. That tail does not like going back into the little slot it comes out of.
The thumper has been doing well up here in Minnesota, having caught both large and small mouth basses, white bass, catfish, northern, walleye, sauger, sunfish and crappies. One week ago today we used thumpers on the Mississippi River and caught sunfish that inhaled the whole bait!