Hey Ron.
Welcome to the forum.
I don't know what bad things people have been saying about the K5 suspension but, it is one of the most overlooked items.
Most people buy a new bike and the first thing they get is a new shiny pipe, a cool chain, hand grips, and some graphics.
In reality, the biggest difference is getting the suspension set up for your weight, riding style, and conditions.
You will go faster with less fatigue.
I'd recommend that you get the EMIG dog bones and have your suspension revalved and resprung.
Then set the sag correctly.
If your not racing in the latest Super Cross arena you will have all the suspension you will ever need.