the zcash zkp is second to none in privacy. with ringsigs the anon set is 3 to 10, usually at the lower end. So it does provide plausible deniability and if that is all you need, then maybe its ok. with the zcash zkp, the anon set is up to 2^28, which is quite a big number.
You really cant compare the two. with a branch factor of 3 to 10 and a relatively small usage, really how hard is it to identify the money flows? especially if the inputs and outputs to the chain are also tracked. You can make a statistical correlation and build models against ringsigs.
With zkp its much more like a blackbox. You can tell the global total in and out of the blackbox, but the zero knowledge part is quite significant. mathematically there is zero information leaked between the zkp -> zkp transactions. ZERO knowledge leaked.
versus "we are not sure which of these 3 are yours"
dont trust me, trust the math. is 2^28 items with zero knowledge leaked in the same category as plausible deniability among 3 to 10?