Henry

"Confederate troops complained that the Union troops could load this gun on Sunday and fire all week."

To use the Henry effectively you need to be close, but when you are close you get shot, and when you get shot you lose your $108 and rare gun.

You will have a very limited supply of Henrys whether you are Confederates or Union. Early game when you have standard muskets with a max range of 250 the Henry will have an extra 30 on them, but later on when the standard rifle has an effective range of 300+ you are going to get shot, a lot.

The level of micro to use the Henry to its' full effect is beyond me, but it can be done and when done right you can route massive brigades in very short order.