I have a JVC in my old Benz - actually the second one I've had in that car. The first one I put in about 15 years ago, bought it used from a co-worker. It finally died about 3 years ago, so I got another JVC, thinking I wouldn't have to re-wire. They had changed the connector...
Its fine, but it has way too many tiny buttons on it, and features I'll never use. Heck, I haven't even used the bluetooth on it, why did I get that? More buttons! The only thing this HD Jensen has that I won't use is Sirius control, so that means fewer, larger buttons, simple, easy to read display, and the HD and waterproofing is just a bonus! I'm just going to use the stock speakers - they're perfectly fine for my purposes. I usually only listen to the stereo on long trips, and then only on interstates in light to moderate traffic - as soon as the traffic gets heavy, the scenery becomes interesting, or the road has cross traffic, etc, the thing gets turned off anyway! I like the idea of simple AM/FM/USB "Geek stick" - what more do I need?
It doesn't appear that I have a "sub woofer" - there's a block off plate behind the grill. If a speaker that size can even be called a woofer - sub or otherwise.