"I have seen too many times where RE in a plan ends badly."
My two cents worth: I have RARELY seen any time where RE in a plan ends well....
Appraisals, RE tax, UBIT, liability insurance (or just liability...), management (someone has to collect rents, pay bills) and the like complicate ownership. Add to that there may be built in tax advantages to owning real estate that get lost due to holding the real estate in a plan (cap gains can get turned into ordinary income, depreciation is lost as a current deduction in a plan, etc...).