As far as I can tell good old fashion jigs work better. I tried them seriously during the spawn last year and the crappie would drag the bobber under and then let the gulp go without being hooked. I could have caught three dozen crappie in the time I wasted testing the gulp minnows. I say wasted but that isn't the way I feel because they are certainly an interesting concept. When I fished with minnows as a kid live minnows would dramatically out fish dead ones. My observation would be that the gulp is close enough to "real" that you get the same reaction as a dead minnow.