That depends upon caliber, and the reliability of the weapon.
With any caliber under a .380/38spl on the power spectrum, I would use fmj, because it is iffy as to whether or not some of those calibers would penetrate enough to incapacitate with JHPs.
If cash was really short and I couldn't buy enough SD ammo to function test for reliability in my carry weapon, I'd rather carry it with FMJ's I trust, that will still do damage, than unreliable ammo I don't trust that may cause a malfunction.
And I wouldn't hesitate to put some 158gr wad-cutters in a .38 special revolver.
It's more about being confident in your weapon, and knowing how to use it properly, than having the latest and greatest.
That being said, given the option, I like JHP.