I'm a former (and perhaps future) liveaboard and my boat (a Ranger 33) was the initial reason for getting the Empeg -- tired of watching CDs slide around the boat (and watching crew step on them!).
Right now I have the Empeg (sled) installed in a panel right next to the original Kenwood AM-FM/cassette unit. They are both connected to a Sony XM-39 automatic switch/relay I bought from Crutchfield (this lets me listen to the radio if I didn't bother to bring the Empeg down to the boat). The switch is connected to a remaindered Soundstream 4+1 channel amp that I bought on-line for cheap (~$130). The amp feeds a pair of KLH home theater speakers (so-so sounds, but low magnetic effect) inside the cabin and a pair of Polyplanar 2-way marine speakers (sound pretty good) in the cockpit. Right now, I have a friend's old 12-inch subwoofer box hooked up.
The Empeg will be great on your boat. When you ask if you can hook it to your PC, the issue with a sled installation is that you have to jump through some hoops to get the ethernet and/or USB to be connected when in a sled. There have been a few threads on the subject here that you can probably find (some with some pics). In the short run, you can just thread ethernet through the opening in the sled and carefully hook it up every time. Others have built a little bracket to hold the RJ45 connector (with retention clip removed) in fixed position in the sled. I am working on making a custom urethane casting that will hold both ethernet and AC power connector for a home sled install. More later on that.
What I may do differently? Well, even with adding a 3rd Type 27 battery last year, the stereo seems to suck a lot of juice when underway (under sail with engine off). The old Kenwood head unit doesn't have the capability to accept the Empeg as an AUX, so I may get rid of the Soundstream amp (the amperage culprit, IMO), add a newer head unit with built-in amplification and run the Empeg through that. In that scenerio, I'd add a self-powered subwoofer with a cutout switch (I don't really care about those low freqs when listening to Tom and Ray).
I'll probably add the Tuner module when available so that I can keep separate home/boat/car profiles and the module may help me hook up a Sony marine remote on the boat (we'll see!)
'Tis the exceptional fellow who lies awake at night thinking of his successes.