I currently have a 1978 25 johnson on my 14' riveted, wide flatbottom. I am looking to upgrade to a newer model and have decided to get a Mercury I am gettig the best price on them $1600 for the 20 and $2000 for the 25. Is the power and speed difference going to be that noticeable between the 2, both r 2 stroke. I'm sure they will have more power than the 1978 I have now, Right??? Or does someone know of a reliable, less expensive . Thanks for all ur help.