Unfortunately, antidysrhythmic medications have significant pro-arrhythmic effects, so "calming" the heart is probably not the best analogy. However, if you are well versed in their mechanisms of action, I would not make a big deal of it. However, some people take these sayings literally. A real common one around here is that "lidocaine numbs the heart." Unfortunately, I feel this shows a fundamental lack of knowledge regarding the mechanism of action of these medications when we distill things down to catch all statements.
The evidence is rather telling in that I gather both agents are equally ineffective at having a functional member of society walk out of the hospital. Therefore, it's a crap shoot IMHO. My bias being that I really do not focus on medications that much in an arrest unless there are clear indications such as a drug overdose or electrolyte imbalance that would potentially benefit from certain treatment modalities. Anecdotally, my experiences with both agents are equivalent.
Take care,
chbare.