Unless you are comparing YC against an actual term sheet in your hand with at least 2X better terms, that YC is overwhelmingly likely a good deal. There might be good reasons not to enter YC for some companies, but the 6% equity is rarely the determining one, even for companies with revenue and sustainable Ramen profits.
pg wrote about this pretty convincingly here: http://paulgraham.com/equity.html
Unless you are comparing YC against an actual term sheet in your hand with at least 2X better terms, that YC is overwhelmingly likely a good deal. There might be good reasons not to enter YC for some companies, but the 6% equity is rarely the determining one, even for companies with revenue and sustainable Ramen profits.