There are a few bankruptcy law firms that handle consumer cases that practice on a regional or national basis. While there is nothing wrong with a law firm being large, some of them that handle consumer bankruptcy cases become large at the expense of properly handling their client's cases, and try to maximize profits at the expense of minimizing the amount of service that they provide.
Given the choice, my recommendation is that you hire a consumer bankruptcy lawyer that lives and practices locally, and takes on a reasonable number of cases. Your case may get "lost in the shuffle" in a large "mill" law firm, or worse. See the Memorandum Opinion in the case of In re Bradley, Case No. 09-36608, in the U.S. Bankruptcy Court for the Southern District of Texas, Houston Division.