Ask HN: Equity Agreements

When asked about shareholder agreements, can anybody give some insight on the ideal response? Is the #1 reason investors ask so they can make sure that the founders are comfortable with their stake? Are they understanding if certain founders carry a sizable chunk or does that lead to more questions than answers?

When we originally sat down to go over our percentage breakdown, we considered some of the following: -idea origins -research & development -recruiting/hiring -tech contributions -money invested -time commitment -expertise -future contributions

After talking things through, here was equity breakdown for four co-founders: 60/20/12/8

Do prospective investors just want to know that we've talked things through or would they challenge (e.g.) myself for holding a significant portion more?