I definitely would not say that Yamaha is the better name, both are pretty equivalent IMO, and at this price point, most of what you are going to find is pretty similar regardless of brand.
I have the R15s on loan from a friend at the moment and they are a tiny bit better than the speakers that come with the Onkyo package. IMO, they are good, not great. I'd personally stay away from the Tiny satellites.
If you are looking at the STF-1, I would seriously just consider the HSU VT-12 package with the STF-1 which would be $550 + shipping.
Alternative would be to go with the Polks R15s and CS and an alternative sub for a little less with about the same performance as the STF-1 would be the Onyx X-sub for $199
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