Kabuto isn't actually using sage mode he's using sage transformation
I would say both. Naruto's frog kumite allows him to sense danger at a moment's notice and dodge it, and Kabuto can gather nature energy when moving around.
no Naruto toad SM was stronger, because the old toad was the Rikudos summon.
This. Kabuto's sage mode seems better because Kabuto himself is versatile and has a lot of jutsus. For the most part toad sage mode and snake sage mode are similar, except Kabuto didnt seem to have the enhanced strength toad sage mode grants.you have to realize the reason why kabuto's seemed stronger was because he had implanted himself with multiple dna types, which gave him more abilities. had he not done that, he would have had basically the same abilities as naruto, minus frog katas. we also don't know if it augmented his strength, but imma assume it does. for the most part i'll say they are technically equal, it's just kabuto had more jutsu and he had the advantage of landscape.