The top two bins have holes all over the bottom, as well as holes along the bottom of the sides. A third bin only has holes on the sides near the top. The third bin is a catch basin for leachate.

The 'Top View' in the upper right corner is looking into the bottom of the bin, not at the lid.

The OSCR Jr is a good design, but is more complex than it needs to be. If you can get airflow through the bin the way they describe, it might be worth the effort, otherwise you can take their concept and simplify things a bit.

I have several stacking bin composters made similar to the Oscar Jr. design. My holes are larger, and there are less of them. But it is a good design and works well.
If you search this forum you should find plenty of info on this style of worm bin.

I have made several OSCR Jr's over the past few months. I make them and get them set up with bedding and worms, and give them to friends who want a worm bin. Every time I give one away, I have the friend buy me a new set of rubbermaid bins. So then I make another one.
I don't find it difficult at all, once you figure out the directions, which are not that easy to figure out. I'm still not entirely clear on how they mean for you to do the cover. As best I can tell, you take two lids and make a large opening on the bottom one and cover it with screen, and then fix the second lid to the top one to keep out light, leaving a gap for air to flow between the lids.
It is also easy to get confused about where the holes are in the "reactor" bins, as you also noticed, Matt.
But as I say, now that I have made several of them, they're pretty easy.
One change I have made is to glue the screen to the lid with a hot glue gun rather than anchoring it with strips of wood. The glue gun is very handy, and it only cost me $3.99 at the craft store.
Then I just fasten the two covers together with four little blocks in the corners rather than strips of wood. I use screws for that.
The people I have set up with these OSCR Jr's all seem to be having success so far. So am I with the one I have, but I've only had it going about a month or two.
I filled the first bin with wet cardboard and cow manure and just let it sit for a couple weeks. Then I added a few worms in one corner. I've also been adding garbage occasionally. The worms seem to be doing just fine.
I'd be interested in hearing from anyone who has been using an OSCR Jr for a good long time, to hear how they think it compares to other systems.
mbetts

I purchased the Can O Worms system back in June of this year, and was so pleased with it that I purchased a second one in July. I have a fairly large garden, so I wanted to be able to make a lot of vermicompost. It is a clean system so I am able to keep it in my house, tucked into the corner of a spare room.

However, you may not want to harvest your compost in your house. I made a huge mess. Thank goodness I have tile floors. My husband is going to make a dolly for me to put the systems on so they can be wheeled out in the garage when it comes time to harvest:)

Sandy