don't listen to Zoronarn the 7th skill for any of the weapons r practicly useless the damage isn't that big than the 5th skills for them and the 7th skills r extreamly slow, u die fast with them in pvp, lets say they'd be good in grinding but if u wanna grind fast then DON'T get them.
As for the 6th skills the spped is like the 4th skills, i didn't feel only a little bit slower but not noticeble, 6th skills r worth getting cuz they'r pretty good in pvp