when to use SPs and Hard lures

When do u stick on a SP rather than a hard lure when bass fishing? what do ye guys generally start on and at what stage of flogging would u decide to change...?

I would use weedless SPs over very shallow snaggy weedy ground rather than hard lures.
Also use SPs if fishing over a drop off, let the SP drift down over the edge and hopefully into the jaws of a lurking bass.
SPs also good if fishing into a deepish gulley, retrieved very slowly.

I would generally use hard lures where there is a water depth of about half a meter or greater.
Although if using surface lures the water depth doesn't matter so much.
Hard lures for choppy conditions, I find the SPs get carried on on the waves.

Although a lot of the time I would change between the two to see which is the most effective.