Burst Skill buff numbers

Does somebody know the actual numbers behind the burst skill? I'd love to know if it more worth to go for Burst, Agitator or Weakness Exploit.

|| || |Level 1|On first hit, gain a small temporary attack and element boost, replaced by a larger boost after the fifth hit.| |Level 2|Hit 5 successive times for a moderate stat boost.| |Level 3|Hit 5 successive times for a bigger stat boost.| |Level 4|Hit 5 successive times for an even bigger stat boost.| |Level 5|Hit 5 successive times for a huge stat boost.|