I can't say for Beetlejuice, but I have seen shows from that area of the theatre a few times, and the seats are really bad. I did it once for Mame,just before Angela Lansbury was leaving, which is why I accepted them...those or nothing. Same with Follies early in the run. (I was also 20 years old and if you wanted cheapskates in the beginning of the run, that was where you sat). I love both performances, but had also seen both shows previously, so missing parts of the performance were frustrating, but I had good memories re what I was missing. In the case of Follies, Beautiful Girls would have been terrible for a first time viewer.
Since BJ is not hard to get tickets for, I would pass, unless (a) they are cheap and are all you can afford; or (b) you like looking at the other side of the theatre as much as looking at the stage. Really bad seats for an awfully of shows. Dance numbers are particularly distorted from those seats.