Assuming that the better the guide is at keeping the chain on means the harder it is to un-jam if it does come off (ie in a crash) does that mean you would want one that is simple/quick to remove to free the chain?
Slight jam when I came off but the load of mud/bush that was wedged in there was the cause of the grief.
What that debris caught in the plastic guide itself or just generally between the chainring and frame/backplate?