Barry,
There are pro's and con's to both, trading as a customer, and prop trading. One major pro for prop trading is many firms give you lower commissions since they share in some of your profits. I don't know if this applies in your case but prop firms also give you increased leverage. If your undercapitalized it might be your only way to trade. One drawback to trading prop is that if your firm requires a deposit, your basically trusting this firm to hold your money. If the firm goes bankrupt your money is gone. If your a customer, your funds are SIPC insured. Another drawback to trading prop is that many firms stagger payouts over many months as a deterrent to leaving. If you ever decide to leave you might forfeit a few months earnings.
Hope this helped