I bought one f113 and it took me close to 10 weeks to fine-tune the position, cross0ver points and phase (plus break-in) and all I can say is these are the fastest and best subs I've yet owned. Prior to this I had 2 REL Stentors and had issues with reliability but these JL's seem to be built like a battleship!
(Dealer disclaimer - not for JL at this time)
(Dealer disclaimer - not for JL at this time)