I recently put a Boss Marine round unit with USB and Bluetooth in my 18' Maycraft. It came with (2) 6.5" marine speakers that I installed on the sides of the console. Often in the summer we will take the boats out to a sand bar and beach them and have some beverages while hanging out. I've been happy thus far and the 6.5" speakers are plenty loud to hear even when going down the lake. I think I gave less than $100 on Amazon for the package when it was on sale.

https://www.amazon.com/BOSS-Audio-R...mp;sr=8-4&keywords=boss+marine+round

Having the radio is nice when you're out drowning bait waiting on a big drum. My boat is a do-all...hunt, fish, family, etc so I wanted the radio.