Not quite the J bug for me, but the PY bug.
Flew PY a few years ago on Cathay, and since then, I have always booked PY (when using cash on EVA and AC) for long haul flights as that extra recline and space is just enough to make the seat comfortable and not kill my back. I also would never pay for business simply due to being unable to afford the insane prices they usually charge (7-10k roundtrip from West Coast NA to Asia typically), and upgrade opportunities tend to not appear for me as a PY passenger with no status on relatively full flights.
Redemption-wise, I'm not looking at CPP specifically, but rather the location I want to travel to, and how much it would cost to fly PY, versus using my points and finding a lower redemption in J. Since most of my points were obtained by welcome offers, it made the most sense to me to try J first and work around it if possible, then if not, look at PY that I would have bought anyways to travel there and use points. It also helps that I am flexible on my travel dates so it's easier to achieve the J redemption. In the end, it's all about saving me hard cash by redeeming points that cost less than what a PY seat would cost.