As I have previously posted (more times than anyone else likely wants to hear) the 501 sounds GREAT with my 'Not Spacearm uni. That said, Tom Fletcher has incorporated stabilizer bars within the arm pivot so as to improve lateral stability on that arm. I did have occasion to hear the 501 just this weekend with an OL Silver arm (without Twl mods!) mounted on my Spacedeck and really could NOT tell any appreciable difference between it and the Spacearm on that table. The OL Illustrious, yes - big difference; the Silver, no.
I am totally unfamiliar with your arm, so what I relate may be meaningless to you.
I am totally unfamiliar with your arm, so what I relate may be meaningless to you.