Do high quality models or lots of lowquality models?

Thats a pretty loaded question, can you be more specific?

Do you mean Low Poly models vs High Poly models?
Do you mean Props/Accessories vs Detailed Furniture/Cloth/Stitching etc?

Regarding Quality - it should always be of the highest standard regardless of what you do. If its not at a professional level then its not suited for the market place.

From my own experience Props/Accessories have sold well. They are not necessarily quicker than creating a nice simulated Cloth though - they just require different skill-sets and once you get used to both workflows its a similar time frame. I find when making something photo-real the 'simpler' the object the more small details are noticed if they are not apparent in the model. Rigged Characters I agree require a lot more talent and time - they often sell for much money though so its value based - more time/skill = more money. Its also worth checking the Analytics as to what is of higher 'liquidity'.

You're welcome.

Sorry I don't know how to check how many times someone else's model has sold. I never really thought about it to be honest.