Yep, I'd say it was totally worth it. It's on my road bike with drop bars, and last time the bike was in the shop, my mechanic was nice enough to offer to re-wrap my bar and put the wires inside! So now it's totally sweet. Since I like to have water bottles where water bottles generally go, I got one of those bento boxes (large size) to go on my top tube and my amplifier and my mp3 player fit into that nicely.
(Note that the system is really just an amp, some wires and two weather-resistant speakers that fit into special end-caps.)
My only caveat is that it's a bit of a battery sucker, so rechargeable AA's would be a good thing to invest in, and despite the fact that it has a slide-off battery compartment, I have to unscrew the whole back of the amp to get the battery holder out for changing batteries. They have some sort of re-charging thing, but I didn't bother to buy it.
But, all things considered, I like having stereo speakers to jam to on my rides!