Ok, at a computer instead of my phone.
I have a 2 liter and a 3 liter Deep South barrel that I play around with at home.

Observations/advice/whatever you want to make of it:
1. Clean the barrel out good, with the char and the drilling of the tap and bung hole, there is always some debris on the inside. Rinse & flush it until you don't have little splinters of wood or char sediment visible in a clear glass.
2. Don't over fill the barrel. Keep the fill level to about 75% to 85% of the volume. For example, in my 2L barrel I put n more than a handle in. In my 3L barrel I put no more than a handle and a fifth in. I learned this the hard way with my first 2L barrel - overfilled it, had it aging in the garage last summer, a few staves split. Deep South replaced it for free though, but I won't make that mistake again.
3. Aging process. I aged my first batch of Maker's by filling the barrel and then putting it out in my garage for about a month. After that month, I put it in the fridge for another month. After that I left it at room temp for about a month. To me, this is necessary to simulate the hot/cool/cold/warm/hot cycle of a full season. I'm sure aging will work just fine sitting on your kitchen counter, but to me if you don't have the expansion and contraction of the wood forcing the juice in and out, you aren't getting much aging. This is my result -
On the left is run of the mill, straight out of the bottle Maker's Mark. On the right is aged Maker's (3 months as described above):

The first thing you'll notice is the color of the aged Maker's is several shades darker. Aging in the small barrel imparted a lot of oak flavor on the front end, but it dissipated pretty quickly. There was a lot more body and spice, and it was considerably smoother across the palate from start to finish than what you get from a normal bottle. I was actually pretty impressed, given that I had almost no expectations going in. Basically it turned Maker's from a mixing bourbon to a very good sipping bourbon that didn't require any additives - I drank it neat with no issues.
My second batch was Buffalo Trace. Generally, I like BT much better than Maker's to start with. It's a smoother bourbon across the board with a little bit better profile in my opinion, so I was starting with a better (to me) juice.
With the BT, I aged it for 2 weeks in the garage (hot), 2 weeks in the fridge (cold), 2 weeks on the counter (neutral) and repeated this process again - basically stayed with the overall time frame of 3 or so months, but by reducing the time in each environment I doubled the "seasons" the juice went through. Like the Maker's, there was more oak on the front end of the BT, but not overpoweringly so (caveat: I like oak, so what is not overpowering to me may be to others, and what I think is oaky is also pretty mild to yet others) and it has a very smooth and crisp finish with a lot more vanilla and a hint of spice in between. It has become my house bourbon, so to speak.
I've also aged some Weller Antique in the same manner above and have been somewhat impressed, though I'll admit that the Weller juice is not my favorite for some reason. I haven't figured it out yet, but there is something that I don't enjoy nearly as much as the Buffalo Trace juice.
Right now I have some Weller 12 and Weller Special Reserve in a 40/60 mix (I screwed this up - should have bought Weller Antique instead of Reserve) vatting and aging in my 2L barrel. I just put it in the fridge last weekend for it's first 2 week cold cycle after a week vatting and aging on the counter, so I still have a ways to go with this one.
My next venture is going to be aging some Elijah Craig 12 for 3-4 months. I'm a HUGE fan of EC12 and have high hopes for what some small barrel aging will do to an already outstanding juice.
4. Will you take an ordinary juice and make it as good as a EC21 or Pappy 20? Not on your life. But you can take an ordinary juice like Maker's, Weller or Buffalo Trace and turn it into a very good sipping bourbon with just a few weeks.
5. It's fun, and doesn't cost all that much. If you don't like the end result, you can always mix the juice, so nothing is really going to waste. I have a lot of fun seeing what different aging times and combinations do with various bourbons, which is really the point of the whole experiment in my opinion.
6. According to Deep South, a month or so in a small barrel is roughly equivalent to a year in a large barrel in terms of aging. This is due to the increased surface area to volume ratio of a small barrel to a normal 53 gallon barrel from a distillery. Now there is a caveat - small barrels don't have the same contact time, vatting and chemical reactions with sugars and tannins that large barrels do, so I would doubt seriously you can dump some White Lightening into a small barrel and stick it on the shelf for a year and come anywhere close to a good 12 year aged juice from a distillery, so don't think you can. But since you are starting with a juice that has at least 4 years in a large barrel, you can make some pretty substantial improvements in a short time frame.
Go get you a barrel and a $25 bottle of Maker's or Buffalo Trace and give it a whirl and let us know what you think.