You specifically said 'good moonshine'.
Now, leaving aside the rather pathetic opinion that if your product violates the federal tax code then it must, by definition, be "crap" that may blind you, let's look at a decent answer to your question...
Defining "moonshine" as non-commercially produced liquor, there are basically two general kinds. The more commonly-EXPERIENCED variety is a liquor made primarily from table sugar (Dixie Crystal) and is, technically, a form of rum, not whiskey at all. It is produced for profit, of course, as is Buffalo Trace or Parker's Reserve. Unlike those, however, there is a certain degree of contempt for the consumer on the part of the moonshine distiller. This type of liquor is thought of -- by it's producer -- as trash, fit only for extracting a profit from suckers, most of whom the distiller would likely catagorize with a name beginning with "N".
It is everything that Chuck and Mike implied it is.
But, as you can probably guess from the legal definition that Chuck pointed out, the term "moonshine" also applies to ANY non-commercial (and therefore, non-tax-paid) liquor. Including the finest of craft distillers' products, and to the sort of excellent corn whiskey that the same "hootch" distillers produce for home consumption. Unlike some of the authorities who may by quoted here, the Goddess and I have enjoyed many hours sipping truly excellent "whiskey" (doesn't always conform to legal definitions) with people who make it available for a very select clientelle.
Mostly (but certainly not always), this is unaged liquor.
Mostly (but certainly not always), this is liquor (whiskey) made from pure corn or pure rye.
Mostly (but certainly not always), this is liquor that is made to be, not a cheaper version of something else, but a unique product in its own right.
Mostly (but ABSOLUTELY not always), something that actually tastes good.
Personally, I think good corn (or rye) whiskey, like Beaujolais wine, is tastiest when drunk young. Chuck enjoys Mellow Mash, which is a corn whiskey aged a couple years (in used oak, since it couldn't be called "corn whiskey" if they used new oak), but I'm not hot on that one. I feel that fresh is better than "slightly" aged. Now, if you take your corn whiskey and age it in NEW oak, for a long time -- like maybe 12 or 13 years -- what you have is pretty much what Old Charter Classic 90 is. Charter is about 80% or more corn (the rest being rye and malted barley -- no sugar) and thus, when aged in new oak, qualifies as straight bourbon. But most bourbon has more rye than that and tastes (a little) different. A moonshiner's "good stuff" would probably also contain a high percentage of corn, and (if aged as you suggest) would likely resemble Old Charter.
There are two important exceptions, however...
(1) Even the best moonshiner's BEST "whiskey" is liable to contain things not allowed in commercial whiskey. Sugar might be one. Maple syrup is likely to be another. Maybe some apples or peaches, too.
(2) If, once upon a time, the moonshiner ever actually DID duplicate Old Charter, he'd have immediately stopped using that recipe. Moonshiners' pride comes from the uniqueness of their product. Only a liquor merchant would find reason to be proud of producing a "taste-alike"