I have a lot of early to mid-50s jazz LPs (including the sublime Ella and Louis recordings) that are not cut to RIAA specs, so adjustable compensation is very appealing as well.
Lately I've been using the ARC Ref Phono 2 with the MP-1. It is v quiet and lets you switch it between RIAA, Decca and Columbia curves. Definitely worth a listen if you can get a loaner.