Store Tp works depending on what Level your enemy is. If you have +20 Tp then if you fight a Too Weak thats realllllllly weak youll get 20 tp per hit. An IT might give you 16-17 per hit. I have the pants and sam traits and I get 14 per hit on an IT and 15-16 on EP and To Weaks. Store Tp is worth it though deffinetly.
Maybe they limit the TP gained. +20 TP seems a little far fetched, if you ask me. But I am not sure if that is true. Oh well...I don't even have SAM yet.
lets see store tp +9 plus the + 2 tp store great katana, and the shinimusha legs, with two attila earrings, you'd have +19 store tp and with the normal sam trait, you'd have +20 store tp.
I heard it adds +.9 tp per swing. Haven't tested myself because i dont have sam high enough to equip. Not a bad choice.. Probably still want jujitsu gi on high evasion mobs though
General opinion on the SAM forum was that every point of store TP gives ~0.5% more TP per gkt hit, also depending on the monster's level compared to yours. It's very hard to find a definitive answer though, I guess I ought to get SAM to 50 and try it out ;)