Well, to me they're apples and oranges. Tama has a completely different sound than Yamaha. Personally, on drum tone alone, I would give it to Yamaha hands down. (Also, Yamaha's finish quality have always been top-notch compared to Tama) Eventhough both companies are Japanese, they seem to approach drum making from completely different angles. I suggest you go down to your local store and try them out. Tama uses diecast hoops (as mentioned previously) that, with their starcast mounting system, puts a lot of weight on top head from the start and therefore tends to make the drum kind of "pitchy". Their tuning range (on their hyperdrive sizes)is also very narrow offering limited tuning range. You're usuall stuck with tuning the drums either really high or really low. Yamaha's range is much larger offering you a larger variety of tuning options, AND drumhead selection. If you like "bite" then Tama sounds like a good choice. On the other hand, if you want variety, full-bodied tone with good bottom end, then go with Yamaha.
If I'm not mistaken, the Yahama Rock Tour ususally doesn't come with a snare and are often sold as 3pc's.( I don't know if this is a deal-breaker for you.)
*Also, I would consider looking into the Pearl Vision VBX and VMX lines of drums or possibly the Sonor Force 3007's. Those two companies are offering a LOT of drum for the $$$ these days. Hope this helps!