I used a MCP 4921 and a MCP3201 in my KOSMO audiohacker project (beware, the schematic in that thread still has many mistakes, I never updated it!!). I would say the chips are okai and I am able to record and loop some seconds with arduino and an external SRAM chip. But I somehow lost motivation for my project and I am currently only using the module as a bit rate reducer (it should have been something like the 2ms freez…) But I would recommend looking at the original audio hacker board which is the one I based my board on, there are already some cool libraries and stuff, like a tiny sampler e.g. 