Love love love ApX. Once had tix for a show, but that was in the days of the infamous "breakdown bus" and they had to cancel. I don't think they've been west of the Mississippi in many years.
J has always answered my email. Make sure you're using the right address. IIRC the one the newsletters come from is a spam trap, so replies to it aren't seen by anyone.
As I've said here before, I am anal about organizing my music to build playlists. I tag parodies with the decade the original was from. Then if I am in the mood for 70s (or whatever) tunes, ApX versions pop up. Of course, they are also tagged with the genre, so ApX punk comes up in the punk playlist, etc.
If they released one more in their "Classics" series, it ought to be with their female guest vocalists. J is great, but I am always excited to hear his daughters or friends on a song.
I've got the one single Petrafried released for free. They did a great job. Never heard of RPM.