Use RaiJinKen (qcf A) against Athena at a "just" blockable distance, she'll try to counter you with a psycho sword, but she'll get hit. 100% efficiency
Use RaiJinKen (qcf A) against AoF and Ikari team at a blockable distance, they'll get hit without response. 90% efficiency
Combos for Benimaru in KoF'98:
Near C/D --> f B --> Shinku Katategoma (qcb A/C)
Near C/D --> f B --> Handou San-dan-geri (qcb B/D)
Near C/D --> f B --> Iai-geri (qcf B/D) --> Handou San-dan-geri (d,u B/D)
(Done at conner) Foot drill (jump, d B/D) --> d B --> Shinku Katategoma (qcb A/C)
AI of Benimaru in KoF'98:
The CPU Benimaru tends to stop all your moves by not only a RaiJenKen in KoF'97, but everyone of his special moves.
He usually do one of the combo stated above when he hit you.
He also like run forward to do a command throw.
In KoF'98, he doesn't like to attack much but play as a perfect defender.
Fighting style of Benimaru in KoF'98:
You should use Benimaru as the same strategy as the CPU use him, except you should attack under suitable conditions.
Also, Benimaru is not as safe as in KoF'97, especially the Shinku Katategoma (qcf A/C),
don't use it unless you're sure it will hit.
The Speed of RaiKoKen and RaiJinKen is a bit slower than in KoF'97.