Not really. The only upside performances have is that they basically come as a mass buff. The buffs Sorc/Wiz/Summ get are more versatile, generally more powerful, and last longer.
Let's take the basic attribute buff line that Sorc/Wiz/Summ get compared to inspire courage. Inspire courage adds a bonus to saving throws against charm and fear. Okay. It also grants +1 to attack and weapon damage. Pretty cool. Except that it does jack for casters, and doesn't help defense. Now take the basic attribute buff line. These add +4 to a stat. Bull's Strength will add +4 strength. That's +2 attack and weapon damage. So it's better than Inspire already. But you can also cast the other buff spells. You can use Cat's Grace, improving AC, Ranged Attack, and Reflex by 2 each, Bear's Endurance, adding 2 temp HP and fortitude, or the 3 mental versions, improving the caster abilities. And Will, for Owl's Wisdom.
Now, I will grant that Inspire improves as the bard gains levels, but you're already saying that if you're bard, you're multiclassing, so you probably won't get the full bonuses out of it. So the Wizard's buffs will turn out better. Add on the buffs that Bard doesn't get in the first place, like Enlarge person, which works out to not only +2 strength, but an improvement to the damage on the weapon, since that also gets enlarged, and others, and the Wizard/sorc/summ just works out to being a better buffer. Plus, Inspire Courage is really the only buff performance Bard get's that's worth a damn, except MAYBE inspire greatness for that HP buff.
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There's always hope for better things in life. But you can't let anything, friend, lover, God himself, be your hope. You have to be your own hope.