Luffy's Gum Gum Bazooka Manual - Use

So I've farmed about 5 of these skill books from the Buggy event.

Just wondering if it's worth using them all on Luffy? (Coz I think his still changes when he evolves??)
That and I'm not really using Luffy as I run a Psy team.

Or if I should just uses it to level my other characters...?

Rice the Skill Books has 2 Effect:
1) Gave 5k EXP to any Character
2) Only to Luffy IF YOU ARE LUCKY, it can evelved the special Moves of Luffy to Level 2 and so it decreases the shifts of waiting for one turn ( Example: From 23 to 22 )

Cool, thanks for the response Alma.

I do realise it's not a definite add to skill lv on Luffy.
Which is why I was asking perhaps it is better used to level other characters (especially when I'm not using Luffy at the moment) rather than spending it all on a character I won't touch.

Plus correct me if I'm wrong but once Luffy evolves to his next form, his attack changes, so you'll lose the benefits anyway?

yeas it is correct and this is the reason that is better use it as 5000 EXP

Thanks Alma. Just wanted to confirm that. Now I can just go nuts with all those books clogging up space