There aren't a ton of reviews for OCS games out there and, as you will notice, many of them address the OCS ruleset as a whole often using a game only to give context to those rules. Here are some of the reviews I felt would be helpful to those curious about getting into OCS.
Burma: Understanding Burma - An Introduction, Is this a wargame for the very heavy Eurogamer? I am a firm believer that playing the Japanese in Burma against an experienced OCS player is the best introduction to OCS. Colin's review only helps consolidate that view for me. This is an excellent review of OCS with an eye towards people unfamiliar with wargames in general.
DAK2:A non-grognard's first look at DAK2 and A non-grognard's second look at DAK2 These two make a nice matched set showing how daunting OCS can be to the outsider but also demonstrating that with a little determination (and willingness to use VASSAL) OCS is a very functional set of rules that allows for fun and engaging gaming. I also think the list of rules mistakes goes a long way towards showing that OCS games can be fun even if you don't understand every nuance of the rules. Indeed, part of the fun is learning how to better use the rules.
Case Blue: User Review Again, this one is more focused on OCS in general than the specific game. This is a bit more advanced and the wall of text makes it a little difficult to process but there is good information here if you take can take the time.
Tunisia: Some complaints. Another overview of OCS, this time with a more critical eye. Some of the complaints are a little nitpicky but overall it is pretty fair. As much as it pains me to say it, OCS isn't for everybody.
Sicily: Triumph and Folly: Small review of a small...ish game This was actually the inspiration for this post. I was surprised in my perusal of OCS games that there aren't more nice, tight game specific reviews like this. This review goes over very nicely what to expect in a campaign game as well as covering what makes Sicily distinctive in the OCS constellation of games.
I would like to extend a challenge to OCS players to put up a few more reviews like this that give some nice insight into a particular game. I found it useful and I'm sure many others will as well. With that in mind, I plan to try to put together something similar in regards to Burma.
As a special bonus, here is calandale's review of Burma:
Video is interesting because I think it becomes naturally more personal because the personality of the reviewer can't help but be right there. This is a nice casual review of the game with some insight into the versatility of OCS in general.