Small new oak charred barrels

I couldn’t find much in the search engine pertaining to aging whiskey.

I’m thinking about getting a 3-5 liter new oak charred barrel to age commercial moonshine, young brown whiskeys that have potential, and possibly scotch & rum.

Does any of you have a barrel in that approx size and age spirits?
How do you like it?
How many times can you use it?
Can it really turn rail whiskey to top shelf?
Do you feel it’s worth the $80 or so?

Thanks!