Are there any disadvantages to naming a FLP as primary beneficiary of an IRA?

The IRA owner is a 63 year old female. IRA valued at $700,000, total estate including IRA = $1,400,000. Her son is 38 and owns a home health car business organized as a FLP. Husband, who she will divorce in 1 year, is contolling partner, and son is a limited partner who runs the business. The mother intends to leave her IRA to her son, then her 2 minor gerandchildren. The son thinks it is wise to name the FLP as beneficiary of mother’s trust.

If the son were the controlling partner of the FLP or a limited partnership and the mother, IRA owner names the partnership as primary beneficiary of her IRA, what are the advantages vs. disadvantages?