It s hard to say what is the best.
You can use elemental sword also, you will still have a good survivability.
After sauro l5 gives +5% atk crt damage+19% str and vit +10 and melee+400. It s hard do do better than that, plus the super hidden who gives 1% def and mdef for 20 str.
I can tell my equipment to give you an idea.
Weapon : sauro l5 2s 2 sauroII rc 5 @320
Armor : boo iniliba d38 mpc3
Add : monty raton d22 mpc4
Accessory : mpc5
Special : ror noid.
AI xtal : sauroII vatendeth cheltil ouvel and malti.
I don't remember exactly but arround 390 str Dex and crt.
As you can see I have survival and mpc abi and 2 "survival" AI. I could do more damage by using grapagos on weapon also.
I just like to balance survivability and dps.
And with this set up at lvl 322 I do around 420k rapid fang on 3i and 110/113k impact blow.
I receive between 18 and 45 damage and 450 from shellbreak.
Hope that will help some others to decide what they want to do.
Maximo has posted a good video for special claw user, so now we know which equipment to use for both build.