I'll be going back to my jets this year. In the last 5 years of having short cores, I've not noticed any increase at all in fish hits with the cores. Maybe even less. I couldn't tell you how many fish I would catch with my jets on boards or in lines. Also, no worries about hitting bottom when in shallower. To me, I think short cores are just a fad that caught on because it was different. I can cut down on the # of rods on the boat too.
Don't kill me, this is my own opinion and I'm not speaking for anyone else!