Both are not perfect I would say, to get a really quick evaluation the hp vs Join date is really easy. For a more detailed evaluation, the KE Ration is probably better but it takes longer to check and it excludes delegation for as far as I know. It would really be nice if these things got integrated into the front ends and there to be a general knowledge giving a stamp to all the blatant extractors. So many still that get very high upvotes by curation initiatives who only really hurt the Hive price and give nothing back.