Nobody likes chain drops, but at the same time nobody really wants to go through adding a chain guide to their bike, even if they have the right tabs on the frame. They can be finicky to install and setup, they add weight and the cost is pretty significant relative to just stopping to pop the chain back onto the crank rings. The Bionicon C-Guide attempts to rectify this with a relatively inexpensive device that can easily be installed, addressing the issue of chain drops.
Inside the package you'll get the chainguide, a set of 3 zip ties and a replacement mount. As you can see from the mount, it has a hollow center allowing you to mount on a chainstay that has a shift cable routed underneath. The addition of the third zip tie is an indication that they have probably had problems with the units coming loose.
There are two main channels to run the zip ties to in order to secure it on the chainstay. Clearly the third was an afterthought and is just supposed to be mounted in the center. The easiest way to install this is with a SRAM chain because you can use the removable links to split the chain for a quick mounting. I recommend getting a SRAM power link regardless - if you have a Shimano chain they will work fine, and they are a lifesaver for chain/chainring maintenance.
Once fully installed, the guide easily routes the chain, swivels as you move between chain rings, and reduces the chain slap on the chainstay. I did not notice any drag when riding. There were zero drops on the front rings once the guide was installed, but I did have one on the back. Typically I was seeing 3-4 drops on the front ring and 3-4 on the back, so this is definitely better than the previous setup. I had also changed the cassette from 32T to 34T, so I added a few extra links to the chain, I believe I can cut that down 2 more links and hopefully get to a zero drop range.
Product: Bionicon C-Guide Chain Guide
Rating (1-10): 7 of 10
Pros: Inexpensive, easy to install
Cons: Feels a bit cheap, there have been reports of the zip ties breaking loose
Configuration: 2x9 crank setup on a Santa Cruz Blur LT2
Verdict: For the cost it is probably a good deal - but that really depends on how durable it is. Time will tell on this one.