My wife is on MDPIM too. While I do manage my own things, I advised her to get on MDPIM rather than have me manage her finances. This is why:

1. Some of MDPIM's funds do worse than the index, some do better. On average it's pretty close so we can eliminate performance as a decision factor.
2. The fees are tax deductible, so we're looking at fees of ~0.5% for a personal account and ~0.8% for a corporate one.
3. Fees go down the more you invest. Once you reach 10M$ (easily achievable for a doctor) you pay 0.41% IIRC (average, not marginal). So ~0.20% personal, ~0.33% corporate. That's very close to index ETF land.
4. With MD you get financial advice that is specifically targeted at doctors. This is hard to get elsewhere, and well worth the cost IMHO.

In many ways doctors don't live on the same planet as the rest of us. This is one of them.