Great spell! 2d4 to an attack is fantastic, however it does not stack with inspire courage, so at what point is it not worth it?

Inspire courage +3

Should I swap it out for something else, Invisibility perhaps?

Even when Inspire Courage is at +3, that's only a 3/16 chance that GI won't roll well enough to do better than that. I'll take an 81% chance of a boost to an attack roll any day, especially knowing that you can make a point of applying it only when you know you (or your ally) were already close to hitting.

It's level 2, which competes with invisibility and mirror image and blur and glitterdust, and silence. I'm not sold. Maybe if you were an archetype without inspire courage it would be useful, but even then I think it would be pretty low on the list. I wouldn't take any bard without inspire courage into combat except an archaeologist, which increases the value of invisibility. Blur drops damage to the BSF by 20% and makes him immune to most sneak attackers. Mirror image is one of the best personal defense spells. Silence can be used as a no save near shutdown for casters. I'd probably take all of them before gallant inspiration unless I was sure the wizard would cover them.

any other thoughts?

Basically I am deciding between that or invisibility.

I do already have greater invis. Basically it would be for out of combat stealthy things

Gallant Inspiration: when you absolutely, positively, have to comfirm that critical hit.

It's level 2, which competes with invisibility and mirror image and blur and glitterdust, and silence. I'm not sold. Maybe if you were an archetype without inspire courage it would be useful, but even then I think it would be pretty low on the list. I wouldn't take any bard without inspire courage into combat except an archaeologist, which increases the value of invisibility. Blur drops damage to the BSF by 20% and makes him immune to most sneak attackers. Mirror image is one of the best personal defense spells. Silence can be used as a no save near shutdown for casters. I'd probably take all of them before gallant inspiration unless I was sure the wizard would cover them.

But most of those work just as well as scrolls. GI needs to be a known spell so you can use it on the fly as an immediate action.

Scrolls are not for spells you'll cast every couple fights, and minute/level buffs get cast as before you kick in a door or when you see a random encounter a significant distance away. In many campaigns that happens almost every adventuring day.

of course I should have scrolls of invis! duh

I find it fairly useful for saving failed skill checks. Acrobatics, escape artist, climb, swim, etc all can have annoying results if failed. And being able to do it after knowing it failed, pretty useful.

Of course making sure the paladins smite attack hit is helpful too. I think it retains its value you very well of your adventuring career.

The average of gallant inspiration is +5. So once Inspire Courage hits +5, it's probably not worth it. This happens at level ... never*.

I love the spell :D

Also note that inspire courage and inspire competence have different effects (combat boosts and skill boost). You cause gallant inspiration to boost whichever one you aren't current,y singing about.