Quote from RAMOUTAR:
Market making is not what is used to be, reform has made it very difficult. Unless you will be trading against orderflow on size desk, your upside may be limited. I made markets for a few months on a small desk before I joined the SOES bandits.
There have been more market makers migrating into the prop arena, not the reverse. One can argue and say go and become a better trader with someone else's money. However, you may have better flexibility as prop first. Ask what the desk's major profit centers are, then take it from there. Good luck to you.