The former will sacrifice your defenses entirely but the 39 speed means you usually only need to bait 1 attack to activate Desperation. With your stats, you'd die to a 59 power physical attack, or 60 power magical attack. For Blue mages, if they have exactly 50, you die, but weaker ones won't land the 1 shot luckily for you.
The latter hits a great Vantage speed of 37 and it offsets the reduced defense stat, but you will get doubled by the fastrer damage tryhards (42 speed needed) and the sword ones will kill you since it will be people like Ryouma or Lyn, Lucina, etc and they all have the 48+ power needed to kill you on a double hit.
Between the 2, you'll likely find more consistent results in L&D and Desperation.