SPDA Single Premium Deferred Annuity as a way to protect capital heading into retirement

I'm 3 years away from retirement and my portfolio is 100% index funds. I'd like to start moving some funds out of equities into something more stable to avoid SORR when I start to draw down my IRA. I was thinking just a money market or TBills, but my Fidelity rep suggested a three year SPDA. Apparently if you invest at least 100k, you can get a garenteed 4.3% interest over the 3 years. Obviously this is better than a CD or TBills at the moment. Does this sound too good to be true? I won't have to touch this before the 3 years, and this wouldn't be my sole vehicle for capital preservation. Have others purchased a SPDA through Fidelity?