Better or Worse with a Jack plate ?

[Joker2]

I am going to fill in the notch in my transom as part of my complete transom redo wondering if a Jack plate helps the performance or hinders it? Someone told me it will make the boat ride better in a heavier sea. Just wondering if this is credible info? Thanks

 

[Blu_Lunch]

Jackplate

I'm running a 25 inch shaft on a 20 inch transom with a plate. I like it you can tuck the motor in father the boat come out of the hole faster and planes in a very short distance. I never ran it with out the plate. You can see the plate it's only 3 1/2 thick and rated for 300HP
http://www.wellcraftv20.com/gallery/album115/PDR_0036_1?full=1