mr weazelle

I'm looking at upgrading from stock. I still want to be turn key and reliable. These motors came stock with hyd roller cams. Should I stay with these lifters or switch to hyd flat tappets. What cam specs would you recommend. I'll be changing the intake, carb, cam and installing Stainless Marine exhaust. The boat is equipped with silent choice and the "neighbors" would like me to keep that. Any thoughts?