Personally speaking I'd not feel undergunned with five 88 gr. slugs if that's all I had, though some might.
If I were stoking the cylinder with my own preference however, the situation would dictate what I had in the cylinder. In a vehicle, the first two shots would be birdshot followed by three rounds of .45 LC.
In the home I'd likely have all the chambers filled with .45 LC. Again though, if only limited to birdshot, buckshot and slugs I'd not feel they were inadequate if I used them in the situation they were best suited for.
The .22LR, while not a manstopper or really a suitable first (second, third etc..) choice for being pressed into a SD situation, has still done the business on many goblins and other ne'er-do-wells over several decades.
That being said, I'd much rather have the .410 for SD than the .22LR.