Clients who want to move assets out of their estates while keeping some access are usually offered a spousal lifetime access trust or a self-settled South Dakota asset protection trust. Both can be grantor trusts, both can sit in South Dakota, and both can hold the same assets funded by a completed gift. The real difference is whose access survives.
In a SLAT the household reaches the assets only through the spouse, so if the spouse dies first or the marriage ends, the donor's access ends with it, and unwinding an irrevocable trust after a divorce is hard. In a DAPT the donor is a discretionary beneficiary in his own right, so the plan does not depend on the marriage, a divorce clause costs the donor nothing, and one trust can serve both spouses without inviting the reciprocal trust doctrine.
The full side-by-side is at turnipseed.law.