I feel like I made a mistake using my free summon on Hector instead of Celica because DB4 is a unique inheritable skill, whereas Bold Fighter isn't unique. How long do you think it'll be until other units come out with DB4? Will it be forever unique to Celica?
Considering that Bold Fighter is now in the hands of two units as opposed to one, I really don't see you making a mistake for choosing Hector.
As for the availability of DB4 in the future, chances are IS will want to release the more powerful versions of other Blow (and possibly Stance) skills before including the skill on another unit, so in the short-term no, but long-term maybe.
What the others said and also being unique isn't the only value a skill has. Bold Fighter is an incredibly powerful skill, and honestly goes a lot farther on the right unit (EG ANY tank) than DB4 will, because DB is still going to be a situational skill, and most offensive fighters often want an A skill that ups their speed as well. So just because DB4 is unique in that it's the next level, you won't see people going and replacing it on any offensive unit, whereas any player would love to put Bold fighter on any tank unit if it weren't so damn hard to come by.
All this is to say, don't second guess yourself. I also chose Hector because he's, as always, the standout unit.
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