Cash Management: The Portfolio Manager has relatively greater flexibility to move in and out of cash as and when required depending on the market view. They are allowed to shift from being fully invested in equities to 100% cash at any time. This is one thing most mutual funds cannot do, since their schemes are such that they have to stay invested in equities up to a certain minimum limit (which can be as high as 90%) and cannot go below that, even if they are bearish on the market.
Hedging: A PMS are also allowed to hedge their exposure through derivatives, which helps them in protecting their portfolio from market volatility. Not all mutual funds use derivatives in their investment strategy
Fee Structure: Mutual Funds have a fixed fee structure. PMS providers usually offer more than one option with the same fee structure
Accountability: PMS Managers are directly answerable to the client, whereas mutual fund managers have no such obligations. PMS are much more approachable to the clients. You can meet your portfolio manager, discuss with him his / her strategy and can get all your queries resolved. In fact most of the PMS Managers ensure that they personally stay in touch with the clients. However, this is not possible in mutual fund investment as there may be thousands of investors invested in a particular scheme and the fund manager may not get time to talk and discuss with all of them.