I submitted a theoretical paper to Physical Review Letters, and the editor answered that it can be published in Physical Review but it seems not suitable for a Letter given the Referee responses. Basically, one of the Referee recommends a Letter, while the other recommends a normal Physical Review.
I would like to answer the editor/referee, in order to try to get published as a Letter. What is the best things to do in this situation? Of course, in any case, we should answer all the comments and try to convince the Referee. But is it useful to ask the editor for a third Referee in this case? Is it really hopeless to try to convince the Referee? Will be the third Referee a kind of a lottery?
More details about the specific situation:
One of the Referee praises our work for the interesting results, and for the clarity and readability of the manuscript. Also they say that it would stimulate new experiments, and recommend the publication as a Letter, after some minor points are addressed.
The other Referee however has a different opinion. They say that it is difficult to understand, cumbersome, and even raises a fundamental problem about our main result, which in their opinion is in contrast with the existing literature. Also, they say that the measure proposed will not stimulate the experimental community, since that, in their opinion, the measure seems not easy and there is no qualitative advantage in this proposal, compared with other methods.
Now, I and the other coauthors have fixed the manuscript, and we are able to show that our results do not contradict existing literature, and that the measure is possible (a very similar measure has been already done). I should remark that the topic of our manuscript is a phenomenon which has been confirmed very recently in 2 papers using the same experimental technique. Our proposal refers to a different signature of the same phenomenon.
EDIT: I don't want to appeal, since I think that the Refereeing process has been fair, at least so far. Appealing should be reserved only in the case that one has the impression that the Refereeing was kind of unfair, biased, or fundamentally wrong.