I would bet they both would do pretty good on jewelry IF you set them up right and hunt with the right techniques.
Use small sniper coils if you have them, (that will isolate targets around trash better than larger coils and avoid some masking), but no matter what coil you use go extremely slow, overlap heavily, and dig pretty much all targets, good ones and trash.
Chains can come in anywhere and will be disguised as other common signals including trash, and that goes doubly so for gold which I have found from iron to zinc and everything in between.
Next weekend my MD club is having our end of the year annual seeded hunt and if I use my Compadre quickly and effectively, (yes I do have one of those because I am a jewelry hunter most of all, along with a Vaquero and an F2), I will be able to scoop up tons of targets, silver coins and tokens, and if I find the right token I just might be able to win the AT Pro they are giving away.
If so, I will be glad to report back on how good that one is at finding jewelry, once I learn it.