Help and advice needed leveling up Ults!

Hi, as the title says, i need help and advice deciding how to leveling up 6ps Naruto and Sasuke ult.

After saving 5 to 6 months of SBs, i spend 4500 out if 6000 sbs on the new bannel, which was a struggle to get ults for naruto and sasuke as rates are so badddd, only got 1 ult for naruto and 2x for sasuke... so my question is i have enough frogs to level up sasuke ult to Lv8 (currently on lv3), or i can get Naurto (currently lv1) to lv6 max with the frogs i got, the other choice i can do is share the frogs and prob get Naruto and sasuke ult to lv 5 each. What would you do? Got full kit for both and fully max apart from ult. Your advice and time would be appreciated! Thanks!