Actually, I had the chance to fly both JL and CX in business class this year.

What you want to avoid are the routes flown by the old business class on JL. The new shell seats are pretty much identical to CX's, with fractionally better AVOD. I'm not sure which routes don't have the new seats now, though...pretty sure that LAX/SFO/ORD have them.

In flight service I would actually give the nod to JL over CX.

The JL lounges are nothing with nothing; a bit better than an AC but nothing special. Obviously, it doesn't compare with the Wing/Pier -- but, OTOH, for Bangkok connections at least, the layover was 2 hours instead of 4.5, and to be honest, after you've done the Wing/Pier once, I think you'd rather than the 2.5 hours back

Steve