Garsh, that's what I was going to point you too. This is a very common problem that many of us are well aware of for decades now: Sound engineers aren't really good at electronics. However, don't feel really confident in the return product acting any different unless there's a revision change. That capacitor that leaked and is obvious is probably the exact same cap in your replacement and is just waiting to do it all over again.
You can probably dig around here, but it'd be a hard search with all the randomness over the years (Google is better here). I swear the best 4.1 and 5.1 are still Klipsch, but both need simple modifications in their circuits to last very long. 4.1's needed a drop resistor and the 5.1 Ultra's need pretty much re-routing on the board to not only last longer but sound so much better. No one likes to spend $150-$500 on sound systems and find they need to spend more money, but that's life in kicking parts out really. If you're aiming at functionality, you'll more than likely luck out on that Logitech set for 3 years...max. Remember, warranties last how long?
If you're a sound freak, I'd suggest drifting outside of PC-minded forums and find freaks like me telling you how to tweak audio hardware. If you're not a sound freak then dive under Z-based Logitechs and save some money. If you don't have a swappable IC on the front channel of your soundcard, then just pay $50 for your speakers and be happy. I'm not undermining you, but rather having you aim better at what's going on here. A Z series logitech may be high rated somewhere, but you have the ears you were born with. Just like upgrading to the uber mouse suggested by some pro-gamer won't necessarily improve your game.
They all have QC and shit passes too easily across the board. I'm just asking if you need this level of audio in order to even complain beyond "it's broke". I digress...