Its not either or at this point, you need both (as many as possible) solutions. In some regard CO2 storage solutions are better because you can make use of lower priced real estate like ocean floor vs growing plants and forests which take away real estate that can be used for human habitation and agriculture. Also CO2 storage is more stable in time. Like 100 years from now, people might just choose to cut down the forests and just release all that stored carbon back.