Though I cannot give you hard numbers, I have heard from MSTP grads that gaining employment without residency or post-doc may not be in your long-term career interests. True you are graduating debt-free and the notion of spending 3-5 more years earning a paltry $35K may seem galling.
However, though you may be able to crack a 6-digit salary by going straight into industry, you will quickly encounter a glass ceiling. Without board certification to practice medicine nor the extensive research background to run a lab, you will find it difficult to advance in your career.
From my own personal experience, having just earned my PhD, I can tell you that in no way do I feel prepared to run my own lab. First I need to complete a research-oriented residency, leaning heavily on established faculty for support, encouragment, and advice.
However, jobs for MD/PhDs in industry after residency are extensive and favorable.